Showing papers on "Compression ratio published in 1975"

Piston-type internal combustion engine

Abstract: A piston-type internal combustion engine includes a variable valve timing device controlling the timing of the intake valve, and a coupling between the accelerator pedal and the variable timing device for varying the timing of the intake valve in response to the movement of the accelerator pedal, thereby controlling the quantity of the fuel mixture in the cylinder at the time of combustion. The engine also includes means for maintaining a substantially constant compression ratio in the cylinder notwithstanding variations in the engine output. A number of embodiments are disclosed. In one embodiment, the means for maintaining a substantially constant compression ratio in the cylinder comprises an auxiliary cylinder and an auxiliary piston movable therein, the inner end of the main and auxiliary pistons communicating with each other and defining a common chamber with their respective pistons, the auxiliary piston being displaceable within its cylinder to enlarge or decrease the volume of the common chamber.

Single-Cylinder Engine Evaluation of Methanol - Improved Energy Economy and Reduced NOx

Abstract: Comparative testing of pure methanol, methanol/water blends and isooctane in single-cylinder engines has demonstrated that through proper utilization of methanol's fuel-lean combustion characteristics it may be possible to reach CO emissions of the order of 0.1% and NO/sub x/ emission levels of less than 100 ppM in the raw (undiluted) exhaust. Exhaust treatment to remove unburned methanol and partial oxidation products might be required. Concomitant with decreased emissions are specific energy consumption improvements estimated to be in the range of 26 to 45% better than achievable with current gasolines and the associated low compression ratio engines and emission control systems. These energy consumption improvements are obtained by virtue of efficient lean operation and by utilizing the high octane values of methanol/water blends at high compression ratios. Despite these potential end-use technical advantages for methanol, its large scale use as an automotive fuel is precluded for at least one to two decades because of inadequate supply, the need for immense capital expenditures to increase supply and the need for special engine and fuel control designs.

Increasing warm up enrichment as a function of manifold absolute pressure

Abstract: An electronic fuel control system for an internal combustion engine is disclosed capable of providing an enriched fuel/air mixture to the engine as a function of the engine's temperature and the engine's load during the transient warm up period. The fuel control unit embodies a full load warm up enrichment circuit controlling, in response to engine temperatures below a predetermined temperature and engine loads as determined from the pressure in the engine's intake manifold, the quantity of fuel being delivered to the engine. In the preferred embodiment the full load warm up enrichment circuit is a current sink sinking a portion of the current charging the injection timing capacitor in the electronic control unit to increase the duration of the generated injection fuel delivery pulses.

Combustion, knock and emission characteristics of a natural gas fuelled spark ignition engine with particular reference to low intake temperature conditions

Abstract: For various fuel-air mixtures and different compression ratios, the intake temperature was varied over the entire range of 200 F (366 k) down to - 100 F (200 k) when employing a single cylinder spark ignited research engine fuelled with natural gas. Performance data such as knock and ignition limits, the nature and extent of exhaust emission and chamber pressure cyclic variation were obtained. Means were then suggested for the interpretation of the above mentioned data in terms of engine operation on liquefied natural gas. The experimental work confirmed in general the attractive features of the use of natural gas as a fuel in a spark ignition engine operated under extremely cold intake temperature conditions and that emissions of pollutants were not significantly increased.(a) /TRRL/

Engine with combustion wall temperature control means

Abstract: An internal combustion engine is provide with heat pipe capsules integrated into portions of the combustion chamber wall-forming components of the engine such as the pistons and cylinder head and arranged to transmit heat from the portions of the combustion chamber walls formed by the capsules to adjacent cooling fluid systems at rates controlled by the heat pipe capsules to maintain a predetermined wall temperature range adequate to promote combustion while avoiding detonation or coking of fuel on the wall surfaces.

Constant pressure-temperature delayed combustion high compression ratio engine and method

Abstract: A spark ignition internal combustion engine arrangement and method of operation are provided including high compression, in the range between about 17 to 1 and 30 to 1 of a lean mixture of air and fuel of sufficiently high octane to prevent preignition and detonation when compressed, late ignition of the charge, near top dead center, for combustion during the first part of the expansion phase with heat release controlled by the shape of the combustion chamber to obtain essentially constant pressure combustion up to a predetermined maximum temperature with the remaining fuel being burned at substantially constant temperature. This cycle requires a high initial rate of heat release for the constant pressure combustion portion of the burn followed by a much lower rate during the constant temperature portion. A combustion chamber and engine arrangement for operating on the novel cycle are also disclosed.

Internal combustion engine having a variable engine displacement

Abstract: The present invention refers to a four-cycle, internal combustion engine se pistons have variable strokes, the adjustment of the piston displacement and of the fuel consumption being automatically and continuously realized as a function of the drive shaft load torque. The engine uses an axially annular equidistant location of the cylinders in a cylinder block, comprising an odd number of pistons whose connecting rods are connected, by means of ball joints, with a central oscillating ball, diametrically penetrated by a drive shaft, the ball being sustained by two journal bearings mounted in a gliding bracket. The drive shaft is provided at one of its ends with two oppositely mounted sides that can move along two grooves formed in the inner surfaces of a fork provided at the end of an output shaft, another drive shaft end being coupled directly to a planetary reduction gear box for the control of the intake and exhaust valves. The position of the two slides within the guiding grooves and the groove angle determine the central ball amplitude of oscillation, the piston stroke and, implicitly, the piston displacement and the engine compression ratio.

Rotary internal combustion engine

Abstract: Rotary engine construction wherein a lobed rotor cooperates with unique retractable separators to divide the bore into work chambers, the rotor lobes or pistons performing the intake, compression, power and exhaust functions rapidly, efficiently and smoothly, and wherein the simplicity of construction allows the number of firings per rotor revolution, their sequence and the compression ratio to be readily selected for a particular end use. The engine further embodies novel intake and exhaust valves and actuating structure therefor, work chamber inactivation mechanism, and positive oil pumping means.

Divided chamber type diesel engine

Abstract: A divided chamber type diesel engine consisting of a main combustion chamber and a pre-combustion chamber connected to said main combustion chamber through a connecting port, said pre-combustion chamber being provided with a step member on its inner wall for controlling the swirl generated in said pre-combustion chamber during the compression stroke of the engine in order to reduce the NO x emissions in the exhaust gases.

Combustion engine with dual function motor element and rotary valve for cyclical fuel and exhaust metering

Abstract: An internal combustion engine comprises a compression and expansion casing having an operating member adapted to cause volumetric compression of fuel mixture and volumetric expansion of combustion gas and a combustion tube in which combustion of fuel mixture is effected at a constant pressure. The compression and expansion casing also has means communicating with the interior thereof for providing fuel mixture thereto. The combustion tube includes a constant-pressure chamber adapted to communicate with the interior of the compression and expansion casing through a first valve which opens only when the fuel mixture within the compression and expansion casing is in a compressed condition, a combustion-sustaining chamber communicating with the constant-pressure chamber and having an igniter for igniting and sustaining combustion of fuel mixture and a constant-pressure combustion chamber communicating with the combustion-sustaining chamber to cause further complete combustion of the combustion gas from the combustion-sustaining chamber. The constant-pressure combustion chamber is adapted to communicate with the interior of the compression and expansion casing through a second valve which opens only when the operating member of the compression and expansion casing is in an initial portion of its expansion stroke.

Fuel injection controlling system for an internal combustion engine

Abstract: A fuel injection controlling system for an internal combustion engine comprising an oscillator circuit for generating clock pulses having a frequency corresponding to the air-to-fuel ratio of the mixture, a first detecting circuit for generating pulse signals having a time width corresponding to the rate of air flow to the engine, a first multiplier circuit for generating an output corresponding to the product of the air-to-fuel ratio and the rate of air flow in a binary coded form, a second detecting circuit for generating signals having a pulse width proportional to the rotational speed of the engine, a second multiplier circuit for generating an output corresponding to the product of the air-to-fuel ratio and the rate of air flow and the rotational speed of the engine in a binary coded form, and a conversion circuits for generating pulse signals each corresponding to the output of the second multiplier circuit, whereby fuel injection valves are actuated by the output of the conversion circuit.

Variable compression ratio system for I.C. engines - cylinder block is raised or lowered in relation to crank case until equilibrium is reached

Abstract: The cylinder block is tensioned to the crankcase by pull springs whose strength determines the distance between the cylinder block and the crankcase and thus the compression ratio, a damper is provided to off set any fluctuations. The equilibrium or ideal compression relation is caused by the combustion gases in the cylinder, the lower these are, the higher will be the pulling force of the springs thus increasing the compression, which in turn increases the combustion gas pressure. Alternatively the cylinder movement could be actuated by an engine oil pressure dependent servo.

Powertrain and method for achieving low exhaust emission and high fuel economy operation of a combustion engine

Abstract: A vehicular powertrain includes a conventional gasoline internal combustion engine, a continuously variable ratio transmission, and a feedback control system and engine speed sensor for regulating the power produced by the engine to a value selected by the vehicle operator. The feedback control system operates the engine at wide open throttle and a lean burn air-fuel ratio over a wide range of operating conditions of the vehicle, with the control system adjusting the transmission ratio to regulate the engine speed to a value corresponding to the power selected by the operator. As a result of the extensive engine operation at wide open throttle and a lean burn air-fuel ratio, exhaust emissions are held to a low level while fuel economy is significantly increased.

Compression ignition control pressure heat engine

Abstract: A fuel injected heat engine of the reciprocating type wherein a piston moves reciprocally within a cylinder to compress gases for the support of combustion and to be moved by burning gases to turn a crank with torque, there being a low compression storage chamber of substantial volume normally open into the cylinder and closed by upward movement of the piston to withhold gases at combustion supporting temperature, there being a high compression auto ignition chamber of limited volume comprising the upper portion of the cylinder and isolated from said low compression chamber by said piston closure thereof for continued compression of combustion supporting gases by said piston movement to auto ignition temperature, and there being constant volume fuel injection means for injecting fuel at high pressure into the auto ignition chamber and at a progressively diminishing rate as the first mentioned storage chamber is re-opened and as the cylinder pressure decreases during the effective power stroke.

Air-fuel ratio control adjusting system in an internal combustion engine

Abstract: Secondary air is fed into the engine exhaust gas passageway at a position upstream of an oxygen sensor to cause the electric air-fuel ratio control device and the air-fuel mixture generator to provide an air-fuel mixture having an air-fuel ratio lower than a set desired air-fuel ratio during idle and slow speed running of the engine.

A controlling device used for an internal combustion engine

Abstract: PURPOSE: In order to enhance the efficiency of an internal combustion engine and reduce the fuel consumption, devised is an automatic control system by which the generated torque of said engine can be automatically detected with the goal of attaining to the most optimum value of an ignition timing of said engine. COPYRIGHT: (C)1977,JPO&Japio

Method for fueling combustion engines

Abstract: The invention relates to internal combustion engines of the reciprocal type, and more particularly to such engines in which the pressure for Diesel operation can be attained, or in which the power output of an Otto-cycle engine can be increased. The present invention makes possible either a Diesel engine of approximately the same axial crank offset and overall dimensions as an Otto-engine of equal throughput, or an Otto-engine having a higher throughput with slightly increased overall size and axial crank offset. Gas supply pressures are maintained in pressure boosters by two pressure impellers which are synchronized to engine operation, a vertical pressure impeller receiving a fuel-air mixture and the inverted pressure impeller receiving air. A rotary metering pressure booster meters an amount of the fuel-air mixture and forces it under pressure into a pressure retaining chamber above the cylinder chamber ready to be released upon demand. A second rotary metering pressure booster supplying auxiliary air acts to scavenge and cool the cylinders at the end of each power stroke, as the fuel-air mixture is released from the pressure retaining chamber into cylinder chamber, and as engine speed increases an increasing amount of the auxiliary air will be trapped in the cylinder chamber and compressed together with the fuel-air mixture gradually raising the initial compression as it is compressed into the combustion chamber where it is ignited.

Method of and apparatus for controlling air/fuel ratio in internal combustion engine

Abstract: of the Disclosure A method of and apparatus for controlling the air-to-fuel ratio of a combustible mixture in an internal combustion engine of the particular type using mixture control means arranged to regulate the air-to-fuel mixture within a predetermined relatively high range for the purpose of enabling an exhaust cleaning catalytic reactor to perform its maximum function, characterized in that the air-to-fuel ratio is reduced, viz, the mixture is enriched during highly loaded operational conditions of the engine by supplying additional fuel to the mixture supply system of the engine, temporarily disabling the mixture control means during such conditions or diluting the exhaust gases during high load conditions of the engine so that the control means is caused to operate in such a manner as to compensate for the reduced concentration of air in the exhaust gases

Compression ratio adjustment device, 2-cycle engine

Abstract: PURPOSE: Prevention of an extraordinary combustion and stabilization of idle running intended by means of lowering the secondary compression ratio especially when in a low revolution of the engine. COPYRIGHT: (C)1977,JPO&Japio

Effect of Turbocharging on Diesel Engine Noise, Emissions and Performance

Abstract: The overall effect of two methods of turbocharging a direct injection four stroke diesel engine in terms of performance, smoke, noise and gaseous emissions is described. It is shown that the effect of turbocharging is to produce a more socially acceptable engine. Matched turbocharging involving reduced compression ratios produces substantial emissions and combustion noise reductions (up to 16dB) at full load but can increase combustion noise levels considerably (8 dB) at light load. Before full advantage can be taken, methods of controlling the characteristics of turbochargers to maintain short ignition delays at all conditions are required, together with reductions in engine mechanical noise levels. /GMRL/

Fuel supply system for a rotary piston engine

Abstract: In the stratified combustion rotary piston engine of the Wankel-type, wherein individual combustion chambers are charged with a relatively rich fuel-air mixture and a relatively lean fuel-air mixture or air by first and second intake systems, each system incorporating a fuel injection means, at least one of said fuel injection means being actuated for only selected suction strokes of individual combustion chambers so that the overall air/fuel ratio is altered for the individual combustion chambers.

Variable stroke constant compression axial piston engine - comprises adjustable swash plate and axially adjustable cylinder block

Abstract: The engine operates an Otto four-stroke cycle Variation of the stroke is achieved by varying the swash plate angle The swash plate and cylinder block adjustments make it possible to vary the end compression volume linearly with the length of the stroke so as to maintain a constant compression ratio The swash plate angle is preferably adjusted hydraulically, and the swash plate carried on ball bearings Adjustment may be by a rotating piston in the housing, or by a fixed piston via a linkage and axial bearing The fixed piston may operate the adjustment of both swash plate and cylinder block

Two stroke I.C. engine with charging cylinder - charge piston has tubular slide to form two separate chambers

Abstract: An improvement to 2247147, whereby a charging cylinder and piston is arranged parallel to the combustion cylinder and driven by the same crankshaft to provide an air/fuel mixture via transfer ports. The charge piston is divided into two chambers by a cylindrical separator to keep the air and fuel charges separate even when the piston reaches bottom dead centre. Non return valves are fitted to the fuel/air induction feed and the air feed. Compression ratio of the two completely separate chambers can be made variable.

Effect of compression ratio on NOx production by gas turbines

Abstract: Some recently established correlations of mass fraction of NO/sub x/ in the exhaust gases of modern aircraft gas turbines with compression ratio or with maximum combustion temperature do not necessarily imply that a higher NO/sub x/ fraction in the exhaust must be accepted as a result of increased compression ratio and turbine inlet temperature. These data correlations imply near constancy of the residence times in the primary zones of the burners. It is shown that it is possible to decrease residence time while holding the combustor efficiency constant such that for a given combustor design, NO/sub x/ is nearly independent of combustor inlet temperature. Since the requirement for low CO and hydrocarbon efflux at part throttle conditions dictates high combustion efficiency at these conditions, and since combustion efficiency tends to decrease with decreased throttle setting for fixed-geometry combustors, it is suggested that high-pressure ratio engines be designed for minimum primary zone residence time consistent with combustion efficiency at full power, and that satisfactory part throttle combustion efficiency be achieved by either compressor outlet bleed or combustor bypass.

I.C. engine pressure receiver vessel - absorbs gas from combustion chamber at peak pressures and returns afterwards

Abstract: Receiver is designed to smooth out the peak pressures in an internal combustion engine, returning a gases to the combustion chamber after the peaks. It operates at a pressure above that of the engine compression pressure, and can be actuated by mechanical or air spring. Stored pressure from receiver vessel is returned to the combustion chamber at an equalised pressure, which results in reduced noise, compression losses and heating pressures.

A Study on Low Compression Ratio Diesel Engines : 5th Report, Effect of Intake Air Temperature on Burning Rate and Engine Performances

Abstract: The control of the burning rate is very important in a common diesel engine, and is also an important problem especially in a lower compression ratio diesel engine for further improving the noise emission, thermal efficiency etc. In this paper, for the purpose of controlling the initial burning rate, it was tried to investigate experimentally and theoretically the relationship between the intake air temperature and the initial burning rate. And the effects of the intake air temperature on engine performances, startability and Nox emission, were also examined. As to the burning rate, the initial maximum burning rate almost the same as the experimental one could be obtained by calculations using the evaporating theory of droplets and the thermal reaction theory. And the possibility and the extent of controlling the initial burning rate by an increase of the intake air temperature, were made clear.

After burner type I.C. engine - has additional compression chamber which is valve regulated via pressure storage tank

Abstract: The engine has an additional valve which only closes when the piston has completed most of the compression stroke and passed part of the air fuel mixture into an additional compression chamber. This mixture is provided with additional air with or without additional fuel and blown out as a weak mixture into the main combustion chamber during the expansion stroke. The additional valve is closed during the exhaust stroke but opens before the main induction valve in order to effect a scavenging action in the additional compression chamber. The additional compression chamber is supplied with air from a pressure storage tank and regulated by a valve.