Servojet Electronic Systems, Ltd.

Turbodyne Systems, Inc.

Servojet Electronics Systems

Bevan H Johnston

Niels J Beck

James A Pena

Alan R Roach

William E Woollenweber

Edward M Halimi

In a unique turbocharger shaft bearing system, a thrust bearing is provided inboard of the compressor end shaft bearing. Removable parts of the turbocharger housing permit assembly of a first thrust bearing part with an outwardly extending flange forming at least one thrust bearing interface to be fastened to the rotating shaft for rotation therewith and a separate stationary thrust bearing part to be carried by the housing, providing thrust bearing interface for the thrust bearing interface of the rotating first thrust bearing part inboard of the compressor end of shaft bearing. The removable parts can include a separate supporting member for the compressor end shaft bearing. The remainder of the turbocharger housing supports the second shaft bearing adjacent its turbine end and, through the separate bearing supporting member, the first shaft bearing. The thrust bearing can also include a second rotating thrust bearing part carried by and rotating with the rotating shaft and providing an outwardly extending flange adjacent its turbine end spaced from the outwardly extending flange of the first rotating thrust bearing part and forming a second thrust bearing interface so the thrust bearing interface of the first rotating thrust bearing part can engage the separate stationary thrust bearing member on its compressor side while the thrust bearing interface of the second rotating thrust bearing part engages the thrust bearing member on its turbine side. Providing a thrust bearing inward of the compressor end shaft bearing minimizes bearing overhang, allows an increase in distance between the two shaft bearings, and improves bearing systems stability.

Bearing systems for motor-assisted turbochargers for internal combustion

A series of method and apparatus advances in the accumulator-type fuel injector art, applicable to both intensified and unintensified accumulator injectors, which cooperate to provide major improvements in internal combustion engine fuel economy, reduction of noise, and reduction of undesirable exhaust emissions, including smoke, oxides of nitrogen and hydrocarbons. According to the invention, injector needle closure speed is increased for sharper fuel cutoff and better atomization proximate closure and needle closure bounce is minimized to minimize fuel dribble proximate closure by reducing both mass and length of the needle, which can be accomplished by a longitudinally divided needle. Hydraulic damping also damps and cushions both needle closing and needle opening. The accumulator cavity and needle spring cavity are separated, enabling the accumulator cavity to be as small as desired for high accumulator closing pressure, while nevertheless enabling a strong, fast-acting spring to be used, both factors cumulatively contributing to good closure atomization. A two-stage needle lift is provided for first injecting a pilot fuel charge for preignition, and then injecting the main fuel charge, thereby eliminating the usual adverse premixed burning. The injection spray pattern is automatically varied for improved engine efficiency over the engine power spectrum by utilizing a pintle-type injector nozzle which is variably controlled according to the quantity of fuel delivered.

Accumulator fuel injection system

A pressure intensified fuel injector incorporates an overtravel safety feature which prevents fuel flow through the high pressure chamber of the intensifier upon injection nozzle failure, thereby preventing further and uncontrolled injection events in the event of such failure. The overtravel safety feature is preferably formed by dimensioning the high pressure plunger of the intensifier such that, upon overtravel of the plunger in the event of injector nozzle failure, a side surface of the plunger blocks a fuel inlet port of the high pressure cylinder of the intensifier, thereby preventing further fuel flow through the high pressure cylinder. The intensifier having the overtravel safety feature can be used in either accumulator-type or non-accumulator-type injectors.

Fuel injection system having a pressure intensifier incorporating an

A method of reducing undesired premixed burning in an internal combustion engine includes lifting an injector needle of a fuel injector a constant low-lift increment from a valve seat of a valve covers orifice (VCO) nozzle having an injection hole opening into the valve seat, and preventing lifting of the needle beyond the low-lift increment for a sufficient interval of time to inject a relatively small initial fuel charge into the engine from the VCO nozzle, the injection producing a highly atomized, wide-angle spray plume with relatively low penetration. The interval terminates when lifting forces imposed on the needle overcome holding forces imposed on the needle by a stop plate which has opposed first and second surfaces exposed to an ambient fluid pressure and to a fluid vapor pressure, respectively. A subsequent step includes lifting the needle to a higher lift position to inject a main fuel charge into the engine, the main fuel charge being injected as a relatively narrow jet having high penetration. The stop plate preferably has opposed rough and smooth flat surfaces orientable such that preventing step will occur when the smooth surface faces downwardly and will not occur when the plate is inverted such that the rough surface faces downwardly.

A series of method and apparatus advances in the accumulator-type fuel injector art, applicable to both intensified and unintensified accumulator injectors, which cooperate to provide major improvements in internal combustion engine fuel economy, reduction of noise, and reduction of undesirable exhaust emissions, including smoke, oxides of nitrogen and hydrocarbons. According to the invention, injector needle closure speed is increased for sharper fuel cutoff and better atomization proximate closure, and needle closure bounce is minimized to minimize fuel dribble proximate closure by reducing both mass and length of the needle, which can be accomplished by a longitudinally divided needle. Hydraulic damping also damps and cushions both needle closing and needle opening. The accumulator cavity and needle spring cavity are separated, enabling the accumulator cavity to be as small as desired for high accumulator closing pressure, while nevertheless enabling a strong, fast-acting spring to be used, both factors cumulatively contributing to good closure atomization. A two-stage needle lift is provided for first injecting a pilot fuel charge for preignition, and then injecting the main fuel charge, thereby eliminating the usual adverse premixed burning. The injection spray pattern is automatically varied for improved engine efficiency over the engine power spectrum by utilizing a pintle-type injector nozzle which is variably controlled according to the quantity of fuel delivered.

Growing community of inventors

La Mesa, CA, United States of America

Bevan H Johnston