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Publication numberUS3577726 A
Publication typeGrant
Publication dateMay 4, 1971
Filing dateJul 24, 1969
Priority dateJul 24, 1969
Publication numberUS 3577726 A, US 3577726A, US-A-3577726, US3577726 A, US3577726A
InventorsHarold H Wagner
Original AssigneeCaterpillar Tractor Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fuel system for natural gas turbocharged engine
US 3577726 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 1 13,577,726

[72] Inventor Harold H. Wagner [56] References Cited Peoria, UNITED STATES PATENTS [21] P 1,138,628 5/1915 Cook 123/142 [22] My 1 835 299 12/1931 Greuter 123/142 Patented May 4,1971 [73] Assi ee Cater mar Tractor Co 2,511,348 6/ 1950 K1ttler 60/13 P m 3,052,085 9/1962 Tauschek 60/13 "5" 3,077,189 2/1963 Eamshaw 123/65 3,464,202 9/1969 Wagner 60/ 13 1 Primary Examiner-Douglas Hart [54] FUEL SYSTEM FOR NATURAL GAS AttorneyFryer, Tjensvold, Feix, Phillips and Lempio TURBOCHARGED ENGINE p 5 Chums l Drawmg ABSTRACT: A turbocharged natural gas engine adapted for [52] US. Cl 60/13, use with very low pressure gas by virtue of introducing the gas 123/ 1 19, 123/120, 123/ 142 and combining it with air to provide a combustible mixture up- [51] lnt.Cl. ..F02b 37/00, stream of or on the low pressure side of the turbocharger. F02m 21/04 Safety means are provided to insure against damage by Field of Search 1 3, backfire and against admission of explosive gases to the engine 39.11; 123/142, 119 (C), 120 crankcase.

AFTERCOOLER TD CRANKCASE PATENTED HAY 4 l9?! M2235 EAL INVENTOR HAROLD H. WAGNER Mfg- ATTORNEYS v BY WW FUEL SYSTEM FOR NATURAL GAS TURBOCHARGED ENGINE Natural gas is often available as a low cost engine fuel, but in many cases, the source is of low pressure gas which presents a problem of introducing it into the high pressure air stream of a turbocharged engine. Compressors have been employed to solve this problem but they are costly to acquire and operate and tend to offset the advantage of the low cost fuel. Other problems arise from the use of gas as a fuel in connection with backfiring which occurs in a spark-ignited engine and also in connection with the accumulation of the highly combustible mixture in the engine crankcase.

The present invention overcomes the problems recited above as well as others and will best be understood from the following specification which makes reference to the accompanying drawing.

The drawing is a schematic view with parts in section of mechanism employed in carrying the system of the present invention into practice. 7

in the drawing a conventional-air cleaner is shown at 10 and air flowing from the cleaner is directed through a conduit 12 to the compression section 14 of a turbocharger. A carburetor generally indicated at 16 mixes air and natural gas, the latter entering through a pipe 18. The carburetor will not be described in detail as it is one of several such devices manufactured forthe purpose of combining air and gas and maintaining a proper fuel-air ratio.

The air and gas so combined are directed to the turbocharger and thence through an aftercooler 20, which is also of conventional design, to a backfire relief device generally indicated at 22. A passage 24 of this device communicates with an intake manifold 26 of an engine which is not shown. A butterfly valve 34 in the passage controls the volume of combustible mixture to the engine and is adjusted as by a governor (not shown) or other simple means with which it is connected by linkeage, a part of which is shown at 30.

The present invention incorporates two safety devices, one of which is the backfire relief device. This device has a cover 28 held in place by springs 30, the preload upon which is such that the cover will not be raised by normal engine operating pressures, but will be lifted against the force of the springs to relieve greater pressures experienced upon engine backfire. This relief device includes a metal screen 32 through which the backfire flame would have to pass in order to travel into the vicinity of the combustible mixture being delivered to the engine.

The screen operates in this manner because the heat of the backfire is so dissipated by the large surface area of the screen that ignition of the combustible mixture would not occur to cause damage to parts upstream of the backfire relief device.

Another advantage of the present system is that it prevents accumulation of the combustible mixture in the engine crankcase. The compressor includes lubricated bearings and excess lubricant is caught in a well 36in its housing and conveyed through a conduit 38 to a gas liquid separator generally indicated at 40. The separator comprises a closed container with screens 42 separating it into upper and lower sections. it has an outlet through a conduit 44 which communicates with the intake conduit 12 and gas passing upwardly through the screens 42 deposits oil entrained therewith on the screens from which the oil gravitates to a collection sump in the body of the housing. When the oil level reaches an outlet pipe 46 which communicates with a stand pipe 48, it flows by gravity to the engine crankcase. The stand pipe 48 is vented to atmosphere at its upper end to permit oil to freely enter its lower end. Thus, gaseous fuel which may enter the chamber 36 of the turbocharger through bearings which support the blower shaft passes with the oil to the gas separator 40 and is returned into the fuel stream without danger of entering the crankcase where its ignition could be extremely dangerous.

I claim:

1. in a fuel system for a natural gas turbocharged engine; a turbocharger, conduit means directing air to the turbocharger from the upstream side thereof, in the direction of fluid flow through said turbocharger, means for admitting gas into sard conduit means to provide a combustible fuel mixture upstream of said turbocharger, an intake manifold for said turbocharged engine, passage means connecting said turbocharger and said intake manifold, and a backfire pressure relief device located in said passage means between said turbocharger and said intake manifold to effectively isolate said turbocharger from the harmful efiects of backfiring in said intake manifold.

2. The invention of claim 1 in which the backfire pressure relief device has a wire screen to dissipate heat from backfire gas positioned to prevent flame from moving upstream in the direction of fluid flow through the fuel system.

3. The invention of claim 1 wherein the backfire pressure relief device includes a chamber defined by walls and a cover member which directly separates the interior of said chamber from the ambient and is yieldingly urged to close off said chamber from said ambient.

4. In a fuel system for turbocharged natural gas engine; a turbocharger, conduit means directing air to the turbocharger from the upstream side thereof in the direction of flow through said turbocharger, means for admitting gas into said conduit means to provide a combustible fuel mixture upstream of said turbocharger, a crankcase for said turbocharged engine, a conduit connected between said turbocharger and said crankcase through which turbocharger lubricating oil is drained to said crankcase, and a gas-oil separator to separate any combustible fuel mixture which may pass with said lubricating oil through said conduit.

5. The invention of claim 4 with means for directing the separated fuel mixture back into the system upstream of the turbocharger.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1138628 *Jan 21, 1914May 11, 1915Adam F CookMixing-valve.
US1835299 *Jun 28, 1929Dec 8, 1931Charles R GreuterSupercharging apparatus for internal combustion engines
US2511348 *Jul 26, 1946Jun 13, 1950George M HolleySupercharger control
US3052085 *Nov 21, 1958Sep 4, 1962Thompson Ramo Wooldridge IncControl for exhaust driven supercharger
US3077189 *May 13, 1960Feb 12, 1963Earnshaw Alvin RDiesel engine converted into a twocycle gas engine
US3464202 *Nov 14, 1967Sep 2, 1969Caterpillar Tractor CoDensity limiting turbocharger control system
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3884658 *Apr 18, 1972May 20, 1975Pall CorpAir cleaner for supercharged engines
US3910049 *Jan 30, 1974Oct 7, 1975Garrett CorpFuel trap evacuation system
US5375580 *Sep 8, 1993Dec 27, 1994Air Products And Chemicals, Inc.Internal combustion engine with cooling of intake air using refrigeration of liquefied fuel gas
US5375582 *Dec 3, 1993Dec 27, 1994Mk Rail CorporationMethod and apparatus for regulating temperature of natural gas fuel
US5408978 *May 3, 1993Apr 25, 1995Davis Family TrustGaseous fuel entrainment apparatus and process
US5447142 *Dec 6, 1994Sep 5, 1995Caterpillar Inc.Method and apparatus for maintaining reservoir pressure of a consumable, compressible fuel
US6550461 *Oct 12, 2001Apr 22, 2003Jenbacher AktiengesellschaftInternal combustion engine
US6694944Dec 20, 2001Feb 24, 2004Caterpillar Inc.Rapid compression prechamber for internal combustion engine
US7100582 *Apr 28, 2005Sep 5, 2006Dynamic Fuel Systems, Inc.Propane injection control system and apparatus for vehicles
US7451598Oct 31, 2007Nov 18, 2008Dbt Australia Pty LimitedTurbocharged compression ignition engine
US7765992 *Jun 18, 2008Aug 3, 2010Iwai Trading Co., Ltd.Fuel mixer
US7841322Nov 13, 2008Nov 30, 2010Dynamic Fuel Systems, Inc.Super cooled air and fuel induction system for internal combustion engines
US8534266 *Jul 27, 2007Sep 17, 2013GM Global Technology Operations LLCOil separator for gas-powered combustion engines
US20100012097 *Jul 27, 2007Jan 21, 2010Gm Global Technology Operations, Inc.Oil separator for gas-powered combustion engines
US20140123927 *Nov 4, 2013May 8, 2014Speed Of Air, Inc.Intake plenum pressure release valve
CN101517220BJul 27, 2007Aug 17, 2011Gm全球科技运作股份有限公司Oil separator for gas-powered internal combustion engines
DE3838264A1 *Nov 11, 1988May 17, 1990Motoren Werke Mannheim AgAir filter system for an internal combustion engine
EP0117864A1 *Jan 25, 1984Sep 5, 1984Jenbacher Werke AGCombustion engine
EP1884651A1 *Aug 1, 2006Feb 6, 2008GM Global Technology Operations, Inc.Oil separator for gas operated internal combustion engines
WO1984002955A1 *Jan 25, 1983Aug 2, 1984Jenbacher Werke AgCombustion engine with supercharging device
WO2008014939A1 *Jul 27, 2007Feb 7, 2008Gm Global Tech Operations IncOil separator for gas-powered internal combustion engines
U.S. Classification60/605.1, 123/528, 60/599
International ClassificationF02B33/44, F02M21/02, F02B43/00
Cooperative ClassificationF02B43/00, F02B2710/023, F02B33/44, Y02T10/32, F02M35/10236, F02B37/00, F02M35/10275, F02B29/0406, F02M21/0239, F02M21/0215, F02M21/0293
European ClassificationF02B43/00, F02B33/44, F02M21/02
Legal Events
Jun 12, 1986ASAssignment
Effective date: 19860515