Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
  • F02B33/02—Engines with reciprocating-piston pumps; Engines with crankcase pumps
  • F02B33/06—Engines with reciprocating-piston pumps; Engines with crankcase pumps with reciprocating-piston pumps other than simple crankcase pumps
  • F02B33/22—Engines with reciprocating-piston pumps; Engines with crankcase pumps with reciprocating-piston pumps other than simple crankcase pumps with pumping cylinder situated at side of working cylinder, e.g. the cylinders being parallel
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
  • F02B33/02—Engines with reciprocating-piston pumps; Engines with crankcase pumps
  • F02B33/06—Engines with reciprocating-piston pumps; Engines with crankcase pumps with reciprocating-piston pumps other than simple crankcase pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
  • F02B33/02—Engines with reciprocating-piston pumps; Engines with crankcase pumps
  • F02B33/06—Engines with reciprocating-piston pumps; Engines with crankcase pumps with reciprocating-piston pumps other than simple crankcase pumps
  • F02B33/20—Engines with reciprocating-piston pumps; Engines with crankcase pumps with reciprocating-piston pumps other than simple crankcase pumps with pumping-cylinder axis arranged at an angle to working-cylinder axis, e.g. at an angle of 90 degrees
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B3/00—Engines characterised by air compression and subsequent fuel addition
  • F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition

Definitions

• This invention relates to reciprocating piston internal combustion engines of the type wherein, pumping and power cylinders are operated on two stroke cycles.
• a second type of engine which has pumping and power
• These designs have the pumping cylinder transferring the intake charge through valve timed ports which open into the power cylinder head section.
• U S PAT NO : 3,880,126 utilizes a combustion chamber which is in constant communication with the power cylinder and which has an excessive number of components whilst overall efficiency and power output are severley limited by a poor scavenging efficiency which primarily results from the long transfer scavenging phase required of the design. This further exacerbats the obvious power to weight ratio
• U S PAT NO: 4,458,635 utilizes a valve controlled constant volume combustion chamber which foregoing the supercharging system used that results in a similar said fundamental inefficiency, increases the scavenging and combustion efficiency and hence overall efficiency is also maginally increased. Subsequently, only an average power to weight ratio results whilst an excessive number of componentsis still a major problem.
• the presented invention discloses a novel design of engine which, significantly increases the thermal efficiency and power to weight ratio of all above said types of engines and
• the principal object of this invention therefore describes a engine which has one or more units with a unit having, apumping cylinder with a pumping piston reciprocable therein and two power cylinders which have power pistons reciprocable therein, whilst all said cylinders operate on two stroke cycles and with the pumping piston being driven by means to
• each said transfer port has communication between the said cylinders timed by atleast transfer valve means which, time communication between each transfer port and the power cylinder which it opens into.
• the pumping cylinder induces, thereinto and through a intake valve timed intake port which passes through the said head thereof, atleast a major portion of the intake charge on its increasing volume stroke before on its decreasing volume stroke, the said charge of consecutive cycles thereof is transferred alternately to each of the power cylinders and or their respective combustion chambers through the said transfer valve timed transfer ports.
• the intake charge is atleast 60% of the air used in combustion whilst the head section may include the upper portion of the cylinder walls wherein, less than one third of the cylinder volume is provided.
• a power mainshaft causes reciprocation of the power pistons which relative to each other, are phased or phased about, one stroke apart, whilst a pumping mainshaft causes reciprocation of the pumping piston at the above said rate.
• Valve timed exhaust ports also exit the power cylinders through the said head section andprovide for the expanded gases thereof, to be exhausted
• combustion chambers may be in constant communication with its respective power cylinder or
• a secondary valve which is timed to provide for constant volume combustion for atleast a portion of the time required for said combustion whilst in any case, from hereinafter and above, the opening of a respective transfer valve of a particular power cylinder is refered to as opening into that said power cylinder.
• the pumping piston of a said unit is equallydistanced to the power cylinders thereof and leads the power piston of the power cylinder which the intake charge is to be or is being, transferred into, to the 'top dead centre (from hereinafter refered to as TDC) position by, less than 60 % of the time the power cylinder piston is moving towards the said position whilst the pump mainshaft is driven by means, from the power mainshaft or the output shaft of the engine.
• TDC 'top dead centre
• the respecitve transfer valve is closed before combustion initiates in that power cylinder whilst preferred valve timings which allow for the efficient operation of the said engine are also stated.
• a further object of this invention has the engine just described being optionally modified by various improvements thereto and which have; the pumping cylinder mainshaft being located axially above the power cylinder mainshaft and or, to have the valve train actuating means and or other auxilary device, being driven from means provided on or being located on the pumping cylinder mainshaft or, on the power cylinder mainshaft between the said power cylinders and which provides or a compact engine and unit to be achieved; a variable valve timing mechamism which varies atleast the closing time of the exhaust valve so that its closing time may be varied to allow efficient operation under transient operating conditions.
• combustion chamber types with the transfer and secondary valves being poppet type valves and with desirable locations and timings thereof are further objects of this invention.
• a still further object of this invention has enviable V configurations and turbocharged designs of the novel engine whilst a furtherobject has the pumping cylinder utilizing crankcase compression thereof to improve the charging efficiency thereof.
• FIG 1- is a top schematic view of the preferred design which is a inline single unit and showing the cylinders, ports, combustion chamber and valve opening locations thereof.
• FIG 2- is a cross sectional view taken along line A-A of FIG 1 but around the piston crankshaft mechanism and with the lower crankcase removed.
• FIG 3- is a valve timing diagram of the preferred design in power cylinder crank angle degrees with the lines indicating valve open times and with the TDC position shown thereon being the TDC position of the first power piston.
• FIG 4- Shows an alternative design which has two units, being in a V configuration and utilizing turbocharging and crankcase compression of the pumping cylinder.
• One unit or bank of cylinders is shown as a end view with the other unit shown as a cross sectional view taken along line B-B of FIG 5 but around the piston crankshaft mechanism thereof and with partial hidden detail shown and the lower power crankcase and lower RH side pumping cylinder crankcase being removed.
• FIG 5- is a top schematic view of the sectioned unit of FIG 4 and shows the cylinders, ports, combustion chambers and valve opening locations thereof.
• FIG 6- is a valve timing diagram of the alternative design shown in FIGS 4 and 5 and uses the same features as described for FIG 3.
• FIG 7- is a end shematic view of an alternative V
• each said unit has a pumping cylinder 5 with a pumping piston 16 reciprocable therein and first and second power cylinders, respectively 3 and 4 with first and second power pistons respectively 13 and 14 reciprocable within their respective power cylinders.
• All cylinders of a unit share aparallel axis and a common block 18 and a common head 19, whilst the pumping cylinder is evenly distanced to each of the power cylinders.
• a pumping crankshaft 2 and pumping conrod 17 cause reciprocation of the pumping piston 16 and a power crankshaft 1 and power conrods 15 cause reciprocation of the said power pistons.
• a pump drive gear 7 which is fixed to each of the pumping crankshafts 2,cooperates with, is driven by, and is one half the diameter of, the power crankshaft gear 6 which is fixed to the power
• crankshaft 1 This gear arrangement then provides for the pumping pistons 16 to be reciprocated at and cyclicly operated at, twice that of the power pistons.
• the crankshafts for carrying out all modes of the invention, are of the one piece type whilst all conrods are of the two piece type and bolt on to the respective crankshafts from the undersides thereof, for pivotal movement therearound.
• respective components of the first and second power cylinders are respectively refered to as the first and second said components, or they are refered to as the respective components of the power cylinder of which the description is directed to.
• FIGS 1-3 the preferred design or mode for carrying out the invention, is a naturally aspirated inline version and with the pumping cylinder 5 being located in the middle of the first and second power cylinders, respectively 3 and 4.
• the pumping crankshaft 2 is accessed and held in placeby pumping crankshaft caps 38 which bolt into the engine block 18 whilst the power crankshaft 1 is accessed and held in place by the lower crankcase which is removed in the FIG 2.
• the phasing of the pumping piston 16 relative to the power pistons 13 and 14 has the pumping piston leading the piston of the power cylinder which the intake charge of that particular pumping cylinder cycle will be transfered into, to TDC, by forty power CA degrees.
• the preferred design has all intake, transfer, and exhaust valves being poppet type valves.
• the first and second combustionchambers respectively 22 and 25, remain in constant
• a first transfer valve 8 times communication between the first transfer port 21 and the first power cylinder 3 whilst a second transfer valve 10 times communication between the second transfer port 24 and the second power cylinder 4.
• Two intake valves 12 time
• a first exhaust valve 9 times communication between the first power cylinder 3 and the first exhaust port 23 whilst a second exhaust valve 11 times communication between the second power cylinder 4 and the second exhaust port 26.
• the said exhaust ports lead to an exhaust manifold and eventually to an exhaust pipe whilst the said intake port leads to an intake manifold with air metering means therein provided. All of the said valves are actuated by a single overhead camshaft which has a axis parallel to that of the crankshafts and is
• the said camshaft is not shown on FIG 2 to reduce cluttering thereof and of the major features therof.
• the said camshaft is driven by chain means 46 from the camshaft drive sprocket 39 which is fixed to the pumping crankshaft 2.
• the sprocket on the said camshaft which cooperates with the said chain is a half of the diameter as the said camshaft drive gear, providing for the said camshaft to operate at the same cyclic speed as the power cylinders and as such, single
• variable exhaust valve closing event is obtained by a turning block type of variable valve timing mechanism which is not shown for reasons of undue complexity and which allows for the said valves to close between fifty and sevsnty power CA degreesbefore TDC and depending on engine load and speed. This said variable closing is shown on FIG 3 by the dashed line thereon.
• the engine oil pump supplies the oil to the engine and is driven from the oil pump drive gear 40 which is fixed to the power crankshaft 1 between the power cylinders.
• the intake valves 12 open when the pumping piston moves through to sixty pumping CA degrees after TDC. This allows the compressed intake gas of the previous cycle to expand substantially to atmospheric before the said valves 12 are opened. With the intake valves 12 opened and the pumping piston moving towards its 'bottom dead centre' (which from hereinafter is refered to as BDC)
• the intake air is induced into the pumping cylinders.
• the intake valves 12 are closed and the induction of the intake air ceases.
• one of the transfer valves 21 or 24 begins to open, initiating the transfer phase to the respective power cylinder of which the said open transfer valve opens into.
• the said transfer valve then remains open untill the pumping piston 16 moves through to ten said CA degrees after TDC which is shown in FIG 3 and being thirty five power CA degrees before the piston of the said respective power cylinder reaches TDC.
• the piston of the pumping cylinder then continues towards BDC, and begins a new cycle thereof as is described above and when the intake valves 12 begin to open again at sixty pumping CA degrees after TDC.
• the intake air of the next said cycle is transfered to the other power cylinder and the intake air of the following said5cycle and which is after the said next cycle is transfered to the said respective power cylinder starting a new cycle
• the exhaust valve thereof is open, providing for the later part of the exhaust phase thereof to occur which has the scavenging of the remaining exhaust gases from the said respective cylinder by the transfering intake air.
• the exhaust valve of the said respective power cylinder remains open untill the piston thereof moves to between fifty and seventy power CA degrees before TDC.
• the fuel is injected into the transfer port of the said respective power cylinder during the transfer phase and at low load and or speed, it is mostly injected after the exhaust valve of that power cylinder has closed.
• the alternative design or mode for carrying out the invention has two units which are set in a V configuration and with each said unit being one bank of
• Constant volume combustion chambers which have communication to their respective power cylinders being timed by secondary valves are used in the alternative design with the first said secondary valve being 27 and the second said secondary valve being 28.
• a turbocharger 41 is positioned in the middle of the said V with the exhaust manifolds 23 of all power cylinders communicating thereto whilst the exhaust, ports 23 and manifolds 23 share the same number.
• the pressurised intake manifold 42 leading from the turbocharger 41 communicates with the intake ports of both pumping cylinders whilst the crankcase intake ports 33 of both pumping cylinders is naturally aspirated.
• a single power crankshaft 1 causes reciprocation of all power pistons whilsteach pumping cylinder 5 has its own pumping crankshaft 2.
• a single power crankshaft gear 6 which is fixed to the power crankshaft, cooperates with the pumping cylinder drive gears 7, fixed to each of the pumping crankshafts.
• the phasing of the pumping pistons relative to the power cylinders of a respective unit has the pumping piston leading the said power pistons to TDC by fifty power CA degrees.
• the phasing of the power pistons of the unsectioned unit relative to the said pistons of the sectioned unit has the first power piston 3 of the sectioned unit, leading the said first power piston of the unsectioned unit, by ninety power CA degrees.
• the power crankshaft 1 is accessed and held in place by the lower power crankcase which is removed in the drawings whilst each pumping crankshaft 2 is accessed and held in place by a pumping lower crankcase 47 which is shown on the unsectioned unit of FIG 4.
• the alternative design has all intake, transfer, exhaust and secondary valves being poppet type valves whilst the crankcase intake valves 32 are reed type valves.
• the first combustion chamber 22 and the first power cylinder 3 has communicationtherebetween controlled by a first secondary valve 27 whilst the second combustion chamber 25 and the second power cylinder 4 have communication therebetween controlled by a second secondary valve 28.
• Diesel fuel injection means 37 are mounted into each said combustion chamber whilst ignition therin is caused by the temperature and pressure of the combustible mixture therein.
• Protrusions 31, on the top of each power piston extend upwards so that they substantially atleast, take up the volumes of each secondary port 29 and 30 which result in an efficiency increase of the engine.
• each unit having the same intake, transfer, and exhaust valve and port arrangements and functions, as are described for the preferred design although the positioning of some valves and ports is altered.
• Each said unit has two overhead camshafts which are not shown in the drawings and which are driven by gear means from the pumping cylinder drive gear 7.
• One of two idler gears 43 cooperates with the said gear 7 whilst the another idler gear 44 cooperates with the idler gear 43 and with the camshaft gear 45 which is the same diameter as the power crankshaft gear 6.
• the said camshaft gear 45 is fixed tothe power camshaft which has single camlobes actuating each transfer, secondary, and exhaust valves whilst another gear which is fixed to the said power camshaft cooperates with a gear which is a half the diameter thereof and which is fixed to the pumping camshaft.
• the said pumping camshaft has single camlobes actuating the intake valves with the said diameter difference of the relevant gears providing for the increased cyclic velocity of the intake valves.
• the intake valves 12 begin to open when the pumping piston moves through to seventy pumping CA degrees after TDC. This allows the compressed intake air from the previous cycle to expand substantially to the pressure of the intake manifold before it opens. With the intake valves 12 opened and the pumping piston moving towards its BDC position, the intake air is induced into the pumping cylinder 5. Whilst the said piston 16 is moving towards BDC, the intake air within the crankcase is compressed.
• crankcase intake valves 32 One of the transfer valves opens when the pumping piston is at its BDC positon, to initiate thetransfer phase to the respective power cylinder which the said transfer valve opens into. The said transfer valve then remains open untill the pumping piston has moved to ten said CA degrees after TDC and which is the same as that shown in FIG 6 and being forty five power CA degrees before the piston of the said respective power cylinder reaches TDC.
• the piston of the pumping cylinder then continues towards BDC and begins a new cycle thereof when the intake valves begin to open again at seventy pumping CA degrees after TDC whilst the intake air of the next said cycle is transferred to the other power cylinder and so forth as is described hereinbefore.
• the secondary valve thereof is open providing for the scavenging of the exhaust gases from the combustion chamber thereof.
• the said secondary valve closes when the piston of that respective power cylinder has moved to one hundred and fifteen power CA degrees before TDC.
• the exhaust valve of the said respective power cylinder is open and closes when the piston thereof has moved to forty five power CA degrees before TDC, allowing for nearly all the exhaust gas to be scavenged from the said cylinder except for a small residual portion thereof remaining. This is retained to highly pressurise the remaining gas so that when the secondary valve reopens when the piston thereof is at five power CA degrees before TDC, the pressure in the power cylinder is not significantly lower than that of the combustion chamber thereof which would decrease the thermal efficiency attainable.
• diesel type fuel is injected into the said
• combustion chamber which results in combustion occuring just after the said relevant transfer valve has closed and so that as the said secondary valve thereof is opened, about fifty percent or more of the combustible mass has been combusted.
• the alternative V configuration of FIG 7 has two units being in the said configuration with each said unit being one bank of cylinders for the said engine whilst the pumping cylinders 5 thereof are located to the inside of the said V, and of the power cylinders.
• a single pumping crankshaft 2 causes

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)
• Supercharger (AREA)
• Lubrication Of Internal Combustion Engines (AREA)

Applications Claiming Priority (4)

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ID=25631974

Family Applications (1)

Country Status (3)

Families Citing this family (13)

Citations (3)

Family Cites Families (4)

• 1990
  • 1990-06-15 WO PCT/AU1990/000261 patent/WO1990015917A1/en active IP Right Grant
  • 1990-06-15 EP EP90909109A patent/EP0476010B1/de not_active Expired - Lifetime
  • 1990-06-15 AU AU58184/90A patent/AU638720B2/en not_active Expired

Patent Citations (3)

Non-Patent Citations (1)

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