Showing papers on "Four-stroke engine published in 2002"

Performance and analysis of a 4-stroke multi-cylinder gasoline engine with CAI combustion

Abstract: Copyright © 2002 SAE International. This paper is posted on this site with permission from SAE International. Further use of this paper is not permitted without permission from SAE

An Analytic Model for Cylinder Pressure in a Four Stroke SI Engine

Abstract: An analytic model for cylinder pressures in spark ignited engines is developed and validated. The main result is a model expressed in closed form that describe the in-cylinder pressure development of an SI engine. The method is based on a parameterization of the ideal Otto cycle and takes variations in spark advance and air-to-fuel ratio into account. The model consists of a set of tuning parameters that all have a physical meaning. Experimental validation on two engines show that it is possible to describe the in-cylinder pressure of a spark ignited combustion engine operating close to stoichiometric conditions, as a function of crank angle, manifold pressure, manifold temperature and spark timing.

Strategy and control system for deactivation and reactivation of cylinders of a variable displacement engine

Abstract: A strategy and control system for a variable displacement engine in which cylinder deactivation is obtained by intake cam phasing and exhaust valve deactivation. Fuel control for the engine and spark deactivation are sequenced with valve deactivation to avoid transferring engine exhaust gases to the intake manifold of the engine during a transition between full cylinder operation and partial cylinder operation. Excess air flow through the exhaust system for the engine is avoided during a transition from partial cylinder operation to full cylinder operation. These features achieve stable engine performance during the transition.

Free-piston diesel engine timing and control - toward electronic cam- and crankshaft

Abstract: The free-piston diesel engine replaces the crankshaft of the traditional diesel engine with a power turbine to convert energy from the exhaust gas. Hence, the pistons move freely in the cylinder, mainly influenced by pressure and friction forces. Instead, the motion of the pistons are controlled by an electronic control system - an electronic crankshaft. In addition, the camshaft is replaced by an electronic timing system that triggers and actuates the motion of the valves - an electronic camshaft. In this paper, we describe a hierarchical multirate electronic control system developed for an experimental engine, focusing on piston motion parameter estimation, valve and injector timing, and a piston motion control system. Experimental results with a full scale experimental test engine are included. The results show the effectiveness of the developed control strategy.

Automotive internal combustion engine control system

Abstract: An automotive internal combustion engine control system transmits the output of a starting motor capable of operating as a generator to an internal combustion engine in starting the internal combustion engine, and transmits the output of the internal combustion engine to accessories while the internal combustion engine is in operation. The automotive internal combustion engine control system includes a transmission mechanism that transmits the output of the starting motor to the accessories while the internal combustion engine is stopped for a predetermined condition, transmits the rotation of the drive shaft of the starting motor to the crankshaft of the internal combustion engine at a high first gear ratio in starting the internal combustion engine, and transmits the rotation of the crankshaft of the internal combustion engine to the drive shaft of the starting motor at a low second gear ratio while the internal combustion engine is in operation to operate the starting motor as a generator. The transmission mechanism enables driving the accessories by the starting motor while the internal combustion engine is stopped, smoothly starting the internal combustion engine and efficient energy regeneration while the internal combustion engine is in operation.

Split four stroke engine

Abstract: A four stroke engine including a crankshaft. A power piston within a first cylinder connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke. A compression piston within a second cylinder is connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke. A gas passage interconnects the first and second cylinders and includes an inlet valve and an outlet valve defining a pressure chamber therebetween. An inlet manifold is in fluid communication with an inlet valve of the second cylinder. A bypass valve is in fluid communication with the second cylinder and the inlet manifold, wherein during a compression stroke the bypass valve allows a portion of the air to bypass the inlet valve and exhaust into the inlet manifold to provide a variable compression ratio.

Split four stroke cycle internal combustion engine

Abstract: A four stroke cycle internal combustion engine including a crankshaft, rotating about a crankshaft axis of the engine. A power piston is slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft. A compression piston is slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft. A gas passage interconnects the first and second cylinders. The gas passage includes an inlet valve and an outlet valve defining a pressure chamber therebetween.

Automotive four-cycle engine

Abstract: A four-cycle engine is provided with valve timing adjusters for adjusting opening and closing timing an and an exhaust valve. In medium- to high-speed ranges in medium- to high-load regions of the engine, a closing point (ExC) of the exhaust valve defined as a point of transfer from an acceleration portion to a constant speed portion on its valve lift characteristics curve is set to a point a specific period before an intake top dead center, and an opening point (InO) of the intake valve defined as a point of transfer from a constant speed portion to an acceleration portion on its valve lift characteristics curve is set to a point after the intake top dead center. In addition, the period from the closing point (ExC) of the exhaust valve to the opening point (InO) of the intake valve is made longer in the medium-speed range than in the high-speed range in the medium- to high-load regions of the engine.

Multi-part cooled piston for an internal combustion engine

Abstract: Disclosed is a multipart, cooled piston (1) for an internal combustion engine, comprising a top part (2) and a bottom part (6) which are screwed together via a threaded bolt (26) that is disposed on the top part (2) of the piston and a threaded bore (29) that is incorporated into the bottom part (6) thereof The threaded bore (29) is arranged in an area (31) of the bottom part (6) of the piston, which is embodied in a thin-walled manner such that said area (31) deforms like a disk spring, making it unnecessary to use additional means for securing the mounted connection, such as a counter-nut

Combustion control system for spark ignition internal combustion engine with variable piston stroke characteristic mechanism and variable valve operating mechanism

Abstract: A combustion control system for a spark-ignition internal combustion engine includes a variable piston stroke characteristic mechanism changing a compression ratio of the engine, sensors detecting engine operating conditions, i.e., engine speed and engine load, and at least one of a variable lift and working-angle control mechanism simultaneously continuously changing an intake-valve lift and an intake-valve working angle and a variable phase control mechanism changing an angular phase at a central angle corresponding to a maximum valve lift point of the intake valve. Also provided is a control unit that controls the variable piston stroke characteristic mechanism, and at least one of the variable lift and working-angle control mechanism and the variable phase control mechanism, depending on the engine operating conditions.

Engine control system of internal combustion engine with variable compression ratio mechanism and exhaust-gas recirculation control system

Abstract: A combustion control system for a spark-ignition internal combustion engine includes a variable piston stroke characteristic mechanism changing a compression ratio of the engine, sensors detecting engine operating conditions, i.e., engine speed and engine load, and at least one of a variable lift and working angle control mechanism simultaneously continuously changing an intake-valve lift and an intake-valve working angle and a variable phase control mechanism changing an angular phase at a central angle corresponding to a maximum valve lift point of the intake valve. Also provided is a control unit that controls the variable piston stroke characteristic mechanism, and at least one of the variable lift and working angle control mechanism and the variable phase control mechanism, depending on the engine operating conditions.

Method of stopping and restarting an internal combustion engine with indirect injection

Abstract: The invention relates to a method of stopping and restarting an internal combustion engine with indirect injection. In order to stop the engine in a pre-determined position that facilitates the restart of the engine, the rotation speed and the angular position of the turning part (2, 3) of the engine (1) are measured continuously and the fuel injection is cut off for pre-determined speed and angular position values in relation to the turning part (2, 3). In order to restart the engine using a starter (4), fuel is injected into at least one cylinder of the engine when the piston moving in said cylinder is in a determined position. The spark ignition and/or fuel injection is suspended for pre-determined speed and angular position values in relation to the turning part (2, 3) of the engine (1) and fuel is injected into at least one cylinder of the engine (1) during the last rotation of the engine before it stops. In order to restart the engine, ignition is carried out in at least one cylinder the piston of which is in the compression position when the engine is stopped (1).

Controlled homogeneous-charge compression-ignition engine

Abstract: An engine has a plurality of combustion cylinders with a first piston (3) reciprocably mounted in each of the combustion cylinders in the conventional manner. The engine head has, in communication with each of the combustion cylinders, a cylindrical recess (14) containing a reciprocably mounted second piston (17). On the side of the second piston (17) opposite the combustion chamber is a control chamber (19) with inlets and outlets for controlling movement of the second piston (17). The second piston (17) is used to increase the compression ratio without appreciably reducing the expansion ratio. Alternatively, the second piston (17) may be used as a pump to pump fluid from the control chamber (19). In yet another alternative method of operation, the second piston (17) can be driven outward within the cylindrical recess (14) to an extent which varies in accordance with power demand, thereby varying the compression ratio in accordance with the power demand.

Method and device for operating at least one turbocharger on an internal combustion engine

Abstract: A method and a device for operating at least one turbocharger on an internal combustion engine are disclosed, whereby the control signal for at least one adjustment element on the turbocharger (wastegaste adjuster, electrical auxiliary compressor), is generated, based on the volumetric flow of exhaust gas in the exhaust manifold of the internal combustion engine.

Vehicle engine cooling system with variable speed water pump

Abstract: An engine cooling system and method that will allow an engine water pump to be driven independently of the engine speed. The engine water pump is driven by the engine crankshaft, but includes an electronically controllable pump clutch between the water pump and the crankshaft. A control module electronically controls the engagement of the pump clutch based upon engine and vehicle operating conditions.

Engine cooling system with variable speed fan

Abstract: An engine cooling system and method that will allow an engine cooling fan to be driven independently of the engine speed. The engine cooling fan is driven by the engine crankshaft, but includes an electronically controllable fan clutch between the fan and the crankshaft. A control module electronically controls the engagement of the fan clutch based upon engine and vehicle operating conditions. A water pump for pumping coolant through the engine cooling system may also be driven by the crankshaft of the engine, but with an electronically controlled pump clutch between the engine crankshaft and the water pump.

Engine starter having clutch for connection to engine

Abstract: In an engine starter of the present invention, a driving shaft to output a rotating force and a crankshaft of an engine are linked continuously. The engine starter comprises a one-way clutch to prevent an overrun of an armature after the engine starts. In the one-way clutch, a connecting rotation number in which an inner ring and an outer ring change from a disconnected state to a connected state in a decreasing process of engine revolutions is set above a lower limit of the engine revolutions above which the engine under suspension of the fuel supply is able to get restarted by itself by resuming of fuel supply. Therefore, the engine is always able to get restarted quickly even in a low-rotation range.

Control apparatus and method for vehicle equipped with internal combustion engine

Abstract: A vehicle includes an internal combustion engine that is variably connected, for example, via a mechanical clutch, to a drive train including a transmission. The vehicle also has a functional device operated by a torque generated by the internal combustion engine. A load applied by the functional device on the internal combustion engine when the drive train and the engine are engaged during deceleration of the vehicle and a speed of the internal combustion engine is lower than a predetermined value is controlled such that the load is reduced to a first value lower than a second value of the load applied to the engine when the speed of the internal combustion engine is equal to or higher than the predetermined value.

Engine starting control apparatus

Abstract: An engine starting control apparatus that causes a crankshaft of an engine to rotate reversely to a predetermined position immediately after the engine is stopped to make preparations for next starting of the engine. This action is performed in order to prevent firing by useless ignition upon forward rotation of the crankshaft when the engine is started again. When the engine restarted, the engine starting control apparatus causes the engine to rotate forwardly from the predetermined position. The apparatus includes a starter motor connected to the crankshaft, a reverse rotation means capable of rotating the engine reversely to a predetermined position, an ignition device for igniting the engine in the proximity of the top dead center of a piston, and an ignition suppression device for inhibiting the ignition of the engine for a predetermined period of time after the forward rotation of the engine.

Method and control apparatus for operating an internal combustion engine

Abstract: An internal combustion engine includes a combustion chamber, a crankshaft and inlet and outlet valves. The engine is operated with a method wherein a fresh air charge (rl) of the combustion chamber and the engine rpm (nmot) are considered when computing a pressure (ps) in a region lying upstream of the inlet valve. The computation is done by utilizing at least one of thermodynamic equations and flow equations at at least one discrete time point during a work cycle of the engine. Or, a pressure (ps) in the above region and the rpm (nmot) of the crankshaft are considered when computing the fresh air charge (rl) of the combustion chamber by utilizing one of thermodynamic equations and flow equations at at least one discrete time point during a work cycle of the engine.

Radial internal combustion engine with floating balanced piston

Abstract: A radial piston engine is disclosed wherein power is transferred such that the power take-off is truly balanced, where the piston runs truly parallel to the cylinder walls. This concept reduces wear of the cylinders and piston rings. The engine provides improved gas mileage due to the reduced piston drag. One unique feature is the power take-off from the piston to the flywheels. The design takes power from inside the cylinder compartment, through four transfer arms, to cams that in turn transfer the power to two flywheels. By firing complimentary cylinders 180 degrees at the same time, almost no vibration is noticed. Also, since the cylinders can fire many times per flywheel rotation, the torque which this engine produces is greater other designs. Any number of cylinders is possible. Single cylinders and two cylinder designs with chain power take-offs are also possible for lawnmowers and motorcycles.

Snowmobile equipped with a four-cycle engine and intake structure for snowmobile engines

Abstract: In a snowmobile, a four-cycle engine is mounted in such a manner that its crankshaft is arranged along the body width direction and the central axis of a cylinder(s) is tilted rearward by angle α with respect to the vertical direction of the body, forming a rear tilted engine. At least part of the engine intake system including an air cleaner box and throttle body, connected to the intake port(s) of the engine is accommodated in the space inside the topmost projected portion of the engine hood. Exhaust is led out to the muffler located in front of the cylinder(s) by the exhaust system connected to the exhaust port(s) at the front of the cylinder head. Further, the intake passage is arranged between the engine body and the steering post.

Experimental investigation of controlled auto-ignition (CAI) combustion in a 4-stroke multi-cylinder gasoline engine and drive cycle simulations

Abstract: Controlled Auto-Ignition (CAI) combustion has been realised in a production type 4-stroke multi-cylinder gasoline engine. The engine is based on a Ford 1.71 Zetec-SE 16v engine using substantially standard components modified only in design dimensions in order to significantly increase the trapped residuals. The engine is also equipped with Variable Cam Timing (VCT) on both the intake and exhaust camshafts. CAI combustion is achieved by only using hot internal residuals, and a range of loads between 0.5 and 4 bar bmep and engine speeds between 1000 and 3500 rpm are mapped for CAI fuel consumption and exhaust emissions. The measured CAI results are compared with those of spark ignition (SI) combustion in the same engine at the same speeds and loads. The comparison shows that a more than 30% reduction in bsfc and up to 99% reduction in NOx at low loads can be reached. European New Emission Drive Cycle (NEDC) is simulated for a vehicle equipped with such a CAI combustion engine. Fuel consumption and emissions are compared with an SI engine vehicle undergoing the same drive cycle.

Method, computer programme and control and/or regulation device for operating an internal combustion engine, and internal combustion engine

Abstract: In a method for operating an internal combustion engine, a fuel pump from an output shaft of the internal combustion engine is driven. The fuel pump supplies the fuel into a fuel collecting line, from which it passes through at least one fuel injection device into at least one combustion chamber. The amount of the pumped from the fuel pump into the fuel collecting line is set by a fuel valve means which can at least temporarily connect a pressure side of the fuel pump with a low pressure region and disconnect it from this. To be able to supply small quantities of the fuel pump at high speeds, that a piston pump is used with at least one pumping chamber as a fuel pump, that a plurality of operating ranges 1, ... n, of the internal combustion engine is provided and that at least temporarily in is proposed a first operating range of the internal combustion engine, the delivery space during each c1-th delivery stroke, and in an n-th operating range of the internal combustion engine during each cn-th delivery stroke by the valve device for a certain time is separated from the low-pressure region, wherein: c1, ..., cn are different.

Vehicle-mounted four-cycle engine control device

Abstract: A vehicle-mounted four cycle engine control device which includes an oil pressure detecting sensor that detects a pressure of lubricating oil circulated under pressure in an engine. An oil pressure detecting sensor failure judging system judges whether or not the oil pressure detecting sensor has failed. An engine speed judging system judges whether or not a speed of the engine is equal to or above a predetermined engine speed. A pressure state judging system judges whether or not the lubricating oil pressure detected by the oil pressure detecting sensor continues to be in a state of being lower than a predetermined reference pressure for a predetermined time interval or more. An engine control system reduces the engine speed when it is respectively judged by each of the judging systems that the oil pressure detecting sensor has not failed, that the engine speed is equal to or above the predetermined engine speed, and that the lubricating oil pressure continues to be in a state of being lower than the reference pressure for a predetermined delay time or more.

Single-part cooling channel piston for a combustion engine

Abstract: A single-part cooling channel piston for a combustion engine with a piston head of forged steel comprises a combustion bowl in the piston crown, a ring wall with ring belt and an all-round closed cooling channel level with the ring belt. The piston skirt is connected to the pin bosses attached to the piston head. Inexpensive manufacture together with improved cooling and good form stability of the piston is achieved by providing the cooling channel with holes spread over its circumference towards the piston crown and spaced such that the piston material present between such holes forms supporting ribs for the piston crown.

Engine arrangement for a four cycle engine

Abstract: An arrangement of a four cycle engine is disclosed for use in a vehicle providing a relatively low center of gravity for improved handling and maneuverability. The engine components are located on opposing sides of the longitudinal axis of the vehicle and behind the axis of the crankshaft to move the center of gravity to the middle of the vehicle.

Four cycle engine for marine drive

Abstract: An engine has a combustion chamber An air induction system communicates with the combustion chamber through an intake port An exhaust system communicates with the combustion chamber through an exhaust port Intake and exhaust valves move between an opening position and a closing position of the intake port and the exhaust port, respectively A camshaft actuates either the intake valve or the exhaust valve The camshaft extends generally vertically A camshaft cover member encloses the camshaft together with an engine body of the engine The camshaft cover member defines a slot through which a tool can pass The tool can prevent the camshaft from rotating

A four stroke auto-ignition engine

Abstract: The present invention relates to a method of operating a four-stroke internal combustion engine comprising the steps of: closing an exhaust valve (16) prior to the end of the exhaust stroke to trap combusted gases in a combustion chamber (12); opening an inlet valve (15) during the intake stroke to admit charge into the combustion chamber (12) to be mixed with previously trapped combustion gases; and using an injector (60) to inject fuel into the mixture of the trapped combusted gases and the charge air. In the combustion chamber conditions are generated which enable the mixture of fuel, air and combusted gases to combust by auto-ignition. The injector (60) is additionally used to inject fuel into the trapped combusted gases after closing of the exhaust valve (16) during the exhaust stroke and prior to opening of the inlet valve (15) in the induction stroke.