STURMAN DIGITAL SYSTEMS, LLC Patent applications |
Patent application number | Title | Published |
20130025570 | Digital Hydraulic Opposed Free Piston Engines and Methods - Digital hydraulic opposed free piston internal combustion engines having a pair of free pistons in a pair of cylinders defining a combustion chamber above each free piston. The pair of free pistons is arranged to move within the pair of cylinders with parallel axes of free piston motion, and preferably co-linear axes of free piston motion. At least one hydraulic plunger is under each free piston with each hydraulic plunger in a respective hydraulic cylinder. The hydraulic cylinders are coupled to electronically controlled hydraulic cylinder valving. A controller controls the electronically controlled hydraulic cylinder valving to control the pair of free pistons to have substantially equal and opposite motions. | 01-31-2013 |
20120318239 | Free Piston Engines with Single Hydraulic Piston Actuator and Methods - Free piston engines having a free piston having a first piston diameter in a cylinder with a combustion chamber on a first side of the first piston and a piston rod having a second diameter fastened to a second side of the first piston and extending to a single second piston having a third diameter smaller than the first diameter, but larger that the second diameter, the single second piston extending into a hydraulic cylinder, the second piston having a first hydraulic area defined by the third diameter in a first hydraulic chamber, and a second hydraulic area defined by the area between the third diameter and the second diameter in a second hydraulic chamber, and valving to control the coupling of a high pressure, a low pressure and a reservoir to the first and second hydraulic chambers to control the free piston. | 12-20-2012 |
20110083643 | Hydraulic Internal Combustion Engines - Hydraulic internal combustion engines having at least one combustion piston not mechanically connected to a crankshaft or any other combustion piston, but instead acting on hydraulic plungers through valving that is electronically controlled to control the piston position and velocity, typically through an intake stroke, a compression stroke, a combustion or power stroke and an exhaust stroke. Electronically controlled fuel injection and electronically controlled engine valves provided great flexibility in the operating cycles that may be used, with the engine pumping hydraulic fluid to a high pressure accumulator for use in hydraulic motors or other hydraulic equipment. Embodiments using high pressure air injection to sustain combustion are also disclosed. | 04-14-2011 |
20100299052 | Fuel Systems and Methods for Cold Environments - Fuel systems and methods for cold environments which includes a fuel pump having at least one solenoid coil in an unlaminated magnetic circuit, the fuel pump being disposed in a fuel tank, and a pump drive and pulsing system, the pump drive providing pump actuation current to the solenoid coil and the pulsing system providing short current pulses to the solenoid coil to cause Eddy current losses in the unlaminated magnetic circuit. The method includes, before cranking the engine for starting the engine, providing short, successive current pulses to the solenoid coil to cause eddy current heating in the unlaminated circuit and heating of the fuel in and around the fuel pump, turning on the fuel pump to commence fuel flow to the engine, and cranking the engine for starting after the fuel pump has been turned on. Various features are disclosed. | 11-25-2010 |
20100277265 | Pressure Balanced Spool Poppet Valves with Printed Actuator Coils - Pressure balanced spool poppet valves with printed actuator coils minimize valve leakage and facilitate efficient manufacturing and reliable operation. The spool poppet valves may be configured like a conventional spool valve, but further include a poppet valve at one end of the spool to proved much better sealing when the poppet valve is closed. Various features are disclosed, including pressure balancing for high pressure operation. The printed actuator coils for the spool poppet valves are formed by the interconnection of conductive coils on each of multiple layers of a multiple layer printed circuit board, which circuit board may have a hole there through for accommodation of mechanical and/or magnet requirements, and may include similar printed actuator coils for one or more additional spool poppet valves as well as electronic devices associated with the operation thereof. The spool poppet valves may be advantageously constructed without printed actuator coils, and the printed actuator coils may be advantageously used in actuators of other designs. | 11-04-2010 |
20100229838 | Dual Fuel Compression Ignition Engines and Methods - Dual fuel compression ignition engines and methods that allow compression ignition on gaseous fuels like compressed natural gas, hydrogen and ammonia, yet will run on liquid fuels, including diesel fuels for such purposes as starting or when the gaseous fuel is not available or has been consumed and greater range or operating time is needed. Ignition of fuels having a high self ignition temperature is assured by recirculating high temperature exhaust gas back into the intake charge before compression. Existing engines may be converted to run as a dual fuel engine by replacement of the engine head or heads. Various embodiments are disclosed. | 09-16-2010 |
20100200090 | Spool Valve - Two stage spool valves having, in a single assembly, a first stage spool and a second stage spool. The first stage spool may have a solenoid actuator with a return spring, with the second stage spool having either a hydraulic return or a spring return, or both. The solenoid actuator may be comprised of a stationary structure defining a magnetic flux path, including a stationary structure pole face, that together with a moveable structure, including a moveable structure pole face, define a substantially zero air gap magnetic circuit when the solenoid actuator is actuated, the pole faces of the stationary structure and the moveable structure each being defined in part by soft magnetic iron and in part by hardened steel, the hardened steel of the moveable structure contacting the hardened steel of the stationary structure and the soft magnetic iron of the moveable structure being face to face with the soft magnetic iron of the stationary structure when the solenoid actuator is actuated. | 08-12-2010 |
20100186716 | Multiple Intensifier Injectors with Positive Needle Control and Methods of Injection - Multiple intensifier injectors with positive needle control and methods of injection that reduce injector energy consumption. The intensifiers are disposed about the axis of the injectors, leaving the center free for direct needle control down the center of the injector. Also disclosed is a boost system, increasing the needle closing velocity but without adding mass to the needle when finally closing. Direct needle control allows maintaining injection pressure on the fuel between injection events if the control system determines that enough fuel has been pressurized for the next injection, thus saving substantial energy when operating an engine at less than maximum power, by not venting and re-pressurizing on every injection event. | 07-29-2010 |
20100012745 | Fuel Injectors with Intensified Fuel Storage and Methods of Operating an Engine Therewith - Fuel injectors with intensified fuel storage and methods of operating an engine therewith. At least one storage cavity is provided in the intensifier type fuel injector, with a check valve between the intensifier and the needle chamber and storage cavity preventing loss of injection pressure while the intensifier plunger cylinder is refilling with fuel. This provides very efficient injector operation, particularly at low engine loads, by eliminating the wasted energy of compressing, venting and recompressing fuel for injection. Various injector designs and methods of operating the same in an engine are disclosed. | 01-21-2010 |
20090212126 | Fuel Injector with Boosted Needle Closure - Fuel injectors with boosted needle control providing controlled and rapid needle closure. Boost and drive pistons are provided for hydraulic actuation to controllably close the needle, with the boost piston reaching a mechanical stop before the needle reaches the closed position, with the drive piston alone providing adequate hydraulic force to hold the needle closed. In a preferred embodiment, fuel from the intensifier is coupled to the top of the boost and drive pistons to close the needle, and controllably coupled to the bottom of the boost and drive pistons to allow pressure in the needle chamber to open the needle. Apparatus for control of fuel pressure to the bottom of the boost and drive pistons is disclosed. | 08-27-2009 |
20090199819 | Digital Fuel Injector, Injection and Hydraulic Valve Actuation Module and Engine and High Pressure Pump Methods and Apparatus - Digital fuel injector, injection and hydraulic valve actuation module and engine and high pressure pump methods and apparatus primarily for diesel engines. The digital fuel injectors have a plurality of intensifier actuation pistons allowing a selection of up to seven intensified fuel pressures. The disclosed engine operating methods include using at least one cylinder for a compression cylinder for providing compressed intake air to at least one combustion cylinder. A pressure sensor in each combustion cylinder may be used to indicate temperature in the combustion cylinder to limit combustion temperatures to below temperatures at which substantial NO | 08-13-2009 |
20090183699 | Compression Ignition Engines and Methods - Compression ignition engines and methods of the type wherein the engines operate with one cylinder used as a compression cylinder and a second cylinder used as a combustion cylinder. The engines have all cylinders configured so as to be able to operate as a compression cylinder or a combustion cylinder. In the method of operation, a cylinder may switch its operation between being a compression cylinder and then operate a combustion cylinder. Switching the operation between compression and combustion operation results in an even temperature distribution within the engine, and eliminates the need for special cooling requirements, facilitating retrofit of existing engines. Also use of an air storage tank allows all cylinders to operate as combustion cylinders for short bursts of power. Various other features are disclosed. | 07-23-2009 |
20080277504 | Multiple Intensifier Injectors with Positive Needle Control and Methods of Injection - Multiple intensifier injectors with positive needle control and methods of injection that reduce injector energy consumption. The intensifiers are disposed about the axis of the injectors, leaving the center free for direct needle control down the center of the injector. Also disclosed is a boost system, increasing the needle closing velocity but without adding mass to the needle when finally closing. Direct needle control allows maintaining injection pressure on the fuel between injection events if the control system determines that enough fuel has been pressurized for the next injection, thus saving substantial energy when operating an engine at less than maximum power, by not venting and re-pressurizing on every injection event. | 11-13-2008 |
20080264393 | Methods of Operating Low Emission High Performance Compression Ignition Engines - Methods of operating low emission high performance compression ignition engines. After an expansion stroke during which combustion occurred, a predetermined amount of exhaust gas is trapped in the combustion chamber during the next compression stroke, typically by closure of an exhaust valve. Then fuel is injected into the combustion chamber, the amount of exhaust gas trapped being limited so that that compression stroke does not cause compression ignition. Then typically near the end of the following expansion stoke, air is injected so that compression ignition occurs at or near the end of the next compression stoke. | 10-30-2008 |