Bombardier Recreational Products Inc.

Bruno Schuehmacher

Michel Bernier

Luc Champigny

David Monfette

Normand Lebreux

Roger Rioux

Michel Lefebvre

Xavier-Pierre Aitcin

Sylvain Matte

Sebastien Thibault

Louis Lefebvre

Frederic Desjardins

Jonathan Claveau

Marc Giguere

A method for controlling a two-stroke engine operatively connected to a turbocharger, the turbocharger being in fluid communication with the engine to provide a boost pressure thereto, the method including: comparing one of (i) an actual power output of the engine; and (ii) an exhaust temperature representative of an actual temperature of exhaust gas being discharged by the engine, with a corresponding threshold value thereof; in response to the one of the actual power output of the engine and the exhaust temperature being less than the corresponding threshold value: determining a corrective amount of boost pressure to add to the boost pressure of the turbocharger; and controlling the turbocharger to increase the boost pressure of the turbocharger by the corrective amount. Another method for controlling a two-stroke engine operatively connected to a turbocharger is also disclosed.

Engine assembly and method for controlling an engine

An engine assembly includes: a two-stroke internal combustion engine; a turbocharger operatively connected to the engine, the turbocharger having a compressor and an exhaust turbine; an intake pipe fluidly connected to the engine and to the compressor of the turbocharger; an exhaust tuned pipe fluidly connected to the engine and to the exhaust turbine of the turbocharger; a temperature sensor configured to generate a signal representative of a temperature of exhaust gas flowing within the exhaust tuned pipe; and a controller. The controller is configured to: determine a boost target pressure of the turbocharger based in part on the signal generated by the temperature sensor; and control the turbocharger to provide the boost target pressure to the engine. Methods for controlling an engine are also provided.

A method for starting an internal combustion engine (ICE) having a crankshaft and an electric turning machine (ETM) operatively connected to the crankshaft comprises energizing an absolute position sensor adapted for providing an indication of an angular position of a rotor of the ETM and applying a current to the ETM to generate a sufficient torque to rotate the crankshaft.

Method and system for starting an internal combustion engine

A snowmobile including a frame; at least one ski; an engine with an engine air inlet and an exhaust outlet; a turbocharger including an exhaust turbine, and a compressor. An air intake system includes a first flow path connecting the compressor to the atmosphere; a second flow path connecting the compressor to the engine air inlet; an intake bypass flow path connecting atmosphere to the engine air inlet for bypassing the compressor; and an intake bypass valve for controlling the flow through the intake bypass flow path. An exhaust system includes a third flow path connecting the exhaust outlet to the exhaust turbine; a fourth flow path connecting the exhaust turbine to the atmosphere; an exhaust bypass flow path connecting the exhaust outlet to the atmosphere for at least partially bypassing the exhaust turbine; and an exhaust bypass valve for controlling the flow through the exhaust bypass flow path.

Air intake and exhaust systems for a snowmobile engine

An internal combustion engine (ICE) includes a crankshaft, a cylinder head defining in part a variable combustion chamber of the ICE, a direct fuel injector mounted on the cylinder head, a power source, an electric turning machine (ETM) rotating the crankshaft, an absolute position sensor providing an indication of an angular position of a rotor of the ETM, and an engine control unit (ECU) operatively connected to the absolute position sensor. The ECU controls a delivery of electric power from the power source to the ETM based on the angular position of the rotor of the ETM and causes the direct fuel injector to inject fuel directly in the combustion chamber at a time selected based on the angular position reached by the rotor of the ETM.

A method for controlling delivery of electric power between a power source and an electric turning machine (ETM) comprises applying a start signal to a start-up power electronic switch to cause turning on of the start-up power electronic switch and to allow delivery of electric power from the power source to the ETM via the start-up power electronic switch. A recharge signal is applied to a run-time power electronic switch to cause turning on of the run-time power electronic switch for delivery of electric power from the ETM to the power source via the run-time power electronic switch. A circuit comprises a discharging circuit including the start-up power electronic switch for delivering the electric power when the start-up power electronic switch is turned on. A charging circuit includes the run-time power electronic switch for delivering the electric power when the run-time power electronic switch is turned on.

Monitoring is provided for a drive belt of a continuously variable transmission (CVT) mounted in a vehicle having a motor driving the CVT. A rotational speed of the motor and a power level of the motor are sensed. An abuse indicator for the drive belt is set when, concurrently, the rotational speed of the motor increases at a rate that exceeds a change threshold and the power level of the motor exceeds a power threshold. A level of abuse of the drive belt is calculated based on a speed of the vehicle and on a drive belt temperature. Damage to the drive belt may be prevented by limiting a power output of the motor when an accumulated level of abuse exceeds an abuse threshold. A vehicle having an electronic control unit configured to perform the method is also disclosed.

Method for monitoring a drive belt of a continuously variable transmission and method for preventing damage to the drive belt

A method and a system for starting an internal combustion engine (ICE) having a crankshaft and an electric turning machine (ETM) operatively connected to the crankshaft are disclosed. An absolute angular position of the crankshaft related to a top dead center position of a piston in a combustion chamber of the ICE is determined. Electric power is delivered to the ETM at a first level to rotate the crankshaft. Electric power is then delivered to the ETM at a second level greater than the first level when the piston reaches a predetermined position before the TDC position. Fuel is injected in the combustion chamber after the piston has passed beyond the TDC position. The fuel is then ignited. In an implementation, the ICE is started in less than 110 degrees of rotation of the crankshaft.

A method for controlling a two-stroke internal combustion engine is disclosed. The engine has at least one combustion chamber, at least one direct fuel injector for injecting fuel directly in the at least one combustion chamber, at least one port fuel injector for injecting fuel upstream of the at least one combustion chamber, and at least one exhaust valve. The method has the steps of supplying a first fuel quantity to the at least one combustion chamber, a first ratio of the first fuel quantity being supplied by the at least one port fuel injector; and supplying a second fuel quantity to the at least one combustion chamber when a position of the at least one exhaust valve changes, a second ratio of the second fuel quantity being supplied by the at least one port fuel injector, the second ratio being different from the first ratio.

Internal combustion engine having two fuel injectors per cylinder and control method therefor

A two-stroke internal combustion engine has a crankcase, a cylinder block defining at least one cylinder, a cylinder, a crankshaft, at least one piston, at least one scavenge port, at least one throttle body for supplying air to an interior of the crankcase, at least one direct fuel injector fluidly communicating with at least one combustion chamber for injecting fuel directly in the at least one combustion chamber; and at least one port fuel injector fluidly communicating with the interior of the crankcase for injecting fuel upstream of the at least one combustion chamber. Methods for controlling an engine having at least one direct fuel injector and at least one port fuel injector are also described.

A snowmobile has a frame, an endless drive track, a pair of skis, an engine operatively connected to the endless drive track, an oil tank, an electronic oil pump and an electronic control unit (ECU). The engine has at least one cylinder, a crankcase, and at least one exhaust valve. The electronic oil pump fluidly communicates with the crankcase and the at least one exhaust valve. The oil tank fluidly communicates with an inlet of the electronic oil pump for supplying oil to the electronic oil pump. The electronic oil pump delivers oil from the oil tank to the crankcase and the at least one exhaust valve. The ECU is electrically connected to the electronic oil pump for controlling actuation of the electronic oil pump.

Snowmobile having electronically controlled lubrication

A snowmobile having an electronic oil pump fluidly connected to an oil tank thereof is disclosed. The electronic oil pump is fluidly connected to an engine of the snowmobile for delivering lubricant to the engine. An electronic control unit is electrically connected to the electronic oil pump for controlling actuation of the electronic oil pump. A method of operating an electronic oil pump is also disclosed.

Growing community of inventors

Richmond, CA, United States of America

Bruno Schuehmacher