Cummins Engine Company, Inc.

Cummins Inc.

David A Vittorio

Steven W Reedy

Lester L Peters

Yue Yun Wang

John Franklin Wright

Philip M Dimpelfeld

Rohit Saha

Thomas A Grana

Amarjit S Ghuman

Harold G Weber

Danny R Baker

P Douglas Free

Daniel E Boewe

Canden R Nelson

A vehicle system and method of controlling a vehicle engine are provided. The method includes determining a speed of an engine in the vehicle system including a hydraulic system and a vehicle propulsion system operatively coupled to the engine. The method includes determining that the engine speed is decreasing and an actual engine speed is less than a target engine speed, and determining a current gear setting and one or more operating parameters of the hydraulic system in response to determining that the engine speed is decreasing and the actual engine speed is less than the target engine speed. The method, in response to the current gear setting being engaged and the one or more operating parameters being greater than a predetermined threshold value, includes controlling the engine speed to be higher than the target engine speed.

Dynamic engine speed setting during transient event

A system for controlling turbocharger compressor surge includes a turbocharger compressor fluidly coupled to an engine intake manifold, an exhaust gas recirculation (EGR) valve disposed in-line with an EGR conduit fluidly coupled between the engine intake and exhaust manifolds, means for determining a mass flow parameter, a speed sensor producing a speed signal indicative of turbocharger speed, and a control computer configured to determine a mass flow rate surge value, corresponding to a fresh air mass flow rate above which turbocharger compressor surge is avoided, as a function of the speed signal, and to limit the EGR valve position and VGT position as a function of the mass flow parameter and the mass flow rate surge value to maintain exhaust gas flow through the EGR valve at a flow rate below which turbocharger compressor surge is avoided.

System for controlling turbocharger compressor surge

A system for controlling an operating condition of an internal combustion engine includes a control mechanism responsive to a final control command to establish an engine control parameter, and a control computer configured to estimate a current value of the operating condition as a function of the final control command. The control computer determines an error value as a difference between an operating condition limit and the current value of the operating condition, and determines an operating condition parameter as function of the error value and of the current value of the operating condition. The control computer further determines a control command limit as a function of the operating condition parameter, and determines the final control command as a function of the control command limit and a default control command to thereby limit the operating condition to the operating condition limit.

System for controlling an operating condition of an internal combustion engine

An exhaust valve system for an internal combustion engine including a turbocharger is provided for effectively increasing the turbocharged boost pressure at low load engine conditions thereby effectively improving engine transient response. The exhaust valve system includes an exhaust valve control device operable in a normal timing mode for permitting normal opening of one or more exhaust valves at a normal opening crank angle, and in an advanced timing mode for advancing the timing of the opening of the exhaust valve to an advanced opening crank angle prior to the normal opening crank angle while maintaining the timing of normal closing of the exhaust valves at a normal closing crank angle. In one embodiment, the exhaust valve control device includes a tappet and an actuating fluid supply which operate to move the tappet between expanded and collapsed states to advance the opening of the exhaust valve while permitting normal exhaust valve lift to be introduced prior to peak exhaust valve lift thereby maintaining the normal peak lift and the normal timing of exhaust valve closure. In a second embodiment, the exhaust valve control device includes a dedicated advanced timing mode rocker lever capable of selectively actuating one of a pair of exhaust valves to create an early opening exhaust event prior to a normal exhaust event.

Early exhaust valve opening control system and method

A dedicated compression braking system is provided having at least one engine piston reciprocally mounted within a cylinder for cyclical successive compression and expansion strokes and at least one exhaust valve operable to open in a variable timed relationship with an engine piston compression stroke when the engine is operated in a compression braking mode. The braking system includes an independent exhaust valve actuator assembly, including a braking mode rocker lever and a cam lobe for imparting reciprocable movement to the exhaust valve when the engine is operated in the braking mode. The second exhaust valve actuator assembly includes a braking fluid circuit formed in the braking mode rocker lever and a braking fluid valve and three-way solenoid valve mounted on the braking mode rocker lever for controlling the flow of braking fluid in the braking mode rocker lever during compression braking. The dedicated braking system minimizes the size and weight of the engine and also permits maximum freedom in designing and controlling the operation of the braking system independent of other engine components to maximize the efficiency of compression braking.

Dedicated rocker lever and cam assembly for a compression braking system

An improved engine retarder cycle in which the exhaust valve(s) or a dedicated retarder valve is opened during the compression stroke much earlier than in prior art retarder cycles. By opening the retarder valve earlier, the cylinder pressure is not allowed to build to as high a level as in the prior art, thereby requiring less force to push open the retarder valve. Additionally, increased retarder power is generated by increasing the charge of air that is in the cylinder during the compression stroke. This is accomplished by increasing the turbocharger boost by eliminating wasted flow in and out of the exhaust valves. The increased air mass is also created by incorporating a retarder intake event which opens the valve(s) starting at approximately mid-intake stroke and ending in the first half of the compression stroke. The result is increased retarding work and decreased mechanical loading on the engine.

Engine retarder cycle

A compression braking system for an internal combustion engine having at least one working piston including a master piston operated by an engine component such as a fuel injector actuating mechanism and a slave piston fluidically connected with the master piston to open an engine exhaust valve wherein a pressure relief valve is provided to prevent excessively high pressure supply fluid from a low pressure supply circuit from reaching the high pressure circuit connecting the master and slave pistons thereby preventing inadvertent and excessive movement of the slave piston and possible damage to the engine. The pressure relief valve is fluidically connected to the low pressure supply circuit upstream of a control valve which separates the low and high fluid circuits and opens to vent fluid from the low pressure circuit while allowing continuous, uninterrupted operation of the engine in the braking mode. The pressure relief valve may include a spring biased check valve normally biased in a closed position and movable into the open position whenever the pressure in the low pressure circuit reaches a predetermined level to maintain the fluid in the low pressure circuit below a predetermined pressure level equivalent to a maximum high pressure level in the high pressure circuit capable of moving the slave piston.

Pressure relief valve for compression engine braking system

An improved master cylinder for use with an engine compression braking system includes a two-piece telescoping piston which traps a column of fluid therewithin to establish a solid column or piston for a limited length of travel of the piston. Upon achieving a particular predetermined displacement, the fluid column trapped within the two-piece piston is released, thus rapid piston movement is achieved without overtravel which may open exhaust valves of the engine to a distance wherein interference with the piston occurs. The two-piece telescoping piston is actuated in accordance with an injector pushtube or other combinations such as exhaust or intake valve cam/pushtubes.

Growing community of inventors

Columbus, IN, United States of America

David A Vittorio