2271 results about "Variable displacement" patented technology

A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, selected combustion events are skipped during operation of the internal combustion engine so that other working cycles can operate at a better thermodynamic efficiency. In one aspect of the invention, an engine is controlled to operate in a variable displacement mode. In the variable displacement mode, fuel is not delivered to the working chambers (e.g. cylinders) during selected “skipped” working cycles. During active (“non-skipped”) working cycles, a maximum (e.g., unthrottled) amount of air and an optimized amount of fuel is delivered to the relevant working chambers so that the fired working chambers can operate at efficiencies closer to their optimal efficiency. A controller is used to dynamically determine the chamber firings required to provide the engine torque based on the engine's current operational state and conditions. The chamber firings may be sequenced in real time or in near real time in a manner that helps reduce undesirable vibrations of the engine.

A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. In various embodiments, the appropriate firings are determined dynamically during operation of the engine on a firing opportunity by firing opportunity basis and/or without the use of predefined firing patterns.

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. In the variable displacement mode, selected combustion events are skipped so that other working cycles can operate at better thermodynamic efficiency. More specifically, selected “skipped” working cycles are not fired while other “active” working cycles are fired. Typically, fuel is not delivered to the working chambers during skipped working cycles. In one aspect of the invention, a firing pattern is determined that is not fixed but the active working cycles are selected to favor the firing of working chambers that have recently been fired at least in part to reduce wall wetting losses. In another aspect of the invention, when an active working cycle follows a skipped working cycle in the same working chamber, the quanta of fuel injected for delivery to the working chamber is increased relative to the quanta of fuel that would be delivered to the working chamber when the active working cycle follows another active working cycle in the same working chamber in order to compensate for wall wetting losses that occur during skipped working cycles.

The invention relates to a fracturing transmission and high-pressure discharging system. The fracturing transmission and high-pressure discharging system comprises a chassis and is characterized in that a high-power engine, a transfer case, a plurality of variable displacement plunger pumps and a double-acting fracturing pump are arranged on the chassis, the output end of the high-power engine is connected with the input end of the transfer case, the output end of the transfer case comprises a plurality of power take-off ports, and each power take-off port is connected with one variable displacement plunger pump; the variable displacement plunger pumps drive the double-acting fracturing pump through a hydraulic system. The fracturing transmission and high-pressure discharging system further comprises a system radiator and a heat dissipation plunger pump used for driving the system radiator, and the heat dissipation plunger pump is connected with one power take-off port of the transfer case. The power take-off ports of the transfer case and the variable displacement plunger pumps are arranged annularly. The fracturing transmission and high-pressure discharging system has the advantages that hydraulic driving replaces mechanical transmission, and working vibration is reduced; the layout space of a whole vehicle is saved, and meanwhile, operating efficiency and the stability of the whole vehicle are improved.

Methods and systems are provided for selecting a group of cylinders for selective deactivation, in a variable displacement engine system, based at least on a regeneration state of an exhaust catalyst. The position of one or more valves and throttles may be adjusted based on the selective deactivation to reduce back-flow through the disabled cylinders while also maintaining conditions of a downstream exhaust catalyst. Pre-ignition and knock detection windows and thresholds may also be adjusted based on the deactivation to improve the efficiency of knock and pre-ignition detection.

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In general, a firing control unit determines working chamber firings during operation of the engine that are suitable for delivering a desired engine output. In one aspect, the firing control unit is arranged to isolate the generation of firing sequences having frequency components in a frequency range of concern and to alter the firing sequence in a manner that reduces the occurrence of frequency components in the frequency range of concern. In another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. In preferred embodiments, the frequency characteristics of the filter are variable. In various embodiments, the frequency characteristics of the filter vary as a function engine speed and/or a transmission gear ratio.

A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, selected combustion events are skipped during operation of the internal combustion engine so that other working cycles can operate at a better thermodynamic efficiency. In one aspect of the invention, an engine is controlled to operate in a variable displacement mode. In the variable displacement mode, fuel is not delivered to the working chambers (e.g. cylinders) during selected “skipped” working cycles. During active (“non-skipped”) working cycles, a maximum (e.g., unthrottled) amount of air and an optimized amount of fuel is delivered to the relevant working chambers so that the fired working chambers can operate at efficiencies closer to their optimal efficiency. A controller is used to dynamically determine the chamber firings required to provide the engine torque based on the engine's current operational state and conditions. The chamber firings may be sequenced in real time or in near real time in a manner that helps reduce undesirable vibrations of the engine.

Methods and systems are provided for selecting a group of cylinders for selective deactivation, in a variable displacement engine system, based at least on a regeneration state of an exhaust catalyst. The position of one or more valves and throttles may be adjusted based on the selective deactivation to reduce back-flow through the disabled cylinders while also maintaining conditions of a downstream exhaust catalyst. Pre-ignition and knock detection windows and thresholds may also be adjusted based on the deactivation to improve the efficiency of knock and pre-ignition detection.

A method for improving efficiency and reducing emissions of an internal combustion engine. Variable displacement engine capabilities are achieved by disabling engine valves during load changes and constant load operations. Active cylinders may be operated at minimum BSFC by intermittently disabling other cylinders to provide the desired net torque. Disabling is begun by early closing of the intake valve to provide a vacuum at BDC which will result in no net gas flow across the piston rings, and minimum loss of compression energy in the disabled cylinder; this saving in engine friction losses is significant with multiple disablements.

Methods and systems are provided for monitoring cylinder valve deactivation in an engine operating with a plurality of cylinder valves. One example method comprises, sensing a plurality of cylinder valve positions of a plurality of cylinder valves; and combining the plurality of sensed positions to form a combined cylinder valve signal. The method may further include identifying valve degradation and differentiating valve degradation among the plurality of cylinder valves based on the combined cylinder valve signal and an expected value of the signal, and further based on a crank angle at which the expected value differs from the combined signal.

The technology described herein provides a system and method for automatically increasing the remaining driving range of a vehicle when a low fuel or other condition is detected by altering the operating parameters of one or more vehicle systems to improve propulsion system efficiency and thereby lower fuel consumption. The vehicle range extending system is capable of altering the operating parameters of any vehicle system, including for example variable displacement settings, start-stop technology settings, and HVAC operation. The disclosed technology can also provide information to the driver, suggesting which system operating parameters should be altered to reduce the fuel consumption rate.

Generally, the invention relates to power generation and energy storage. In particular, to systems and methods for providing constant power from hydraulic inputs having widely-varying pressures. More particularly, the invention relates to hydraulic-pneumatic energy storage and recovery systems that include either a fixed or variable displacement hydraulic motor and control systems that allow a user to maintain constant power from the fixed or variable displacement hydraulic motor.

The present disclosure provides systems and methods to detect and reduce any high driveline torsional levels, such as due to the cylinder deactivation in variable displacement system engines or aggressive lock-up strategies for fuel efficiency, in automobile transmissions. The present disclosure utilizes a controller in an automobile to operate a computationally thrifty method for quickly detecting noise and vibration disturbances in the transmission. This quick detection enables fuel economic calibrations that aggressively reduce the disturbances by controlling slip in a launch device of the transmission. As problem disturbances arise, they are detected before occupants notice objectionable behavior. Once detected, the disturbances are reduced, such as by increasing launch device slip, which effectively intercepts the objectionable disturbances before they are transferred through the entire drivetrain. The present disclosure can also apply to launch devices in Dual Clutch Transmissions and Electronically-controlled Manual Transmissions.

Methods and systems are provided for selecting a group of cylinders for selective deactivation, in a variable displacement engine system, based at least on a regeneration state of an exhaust catalyst. The position of one or more valves and throttles may be adjusted based on the selective deactivation to reduce back-flow through the disabled cylinders while also maintaining conditions of a downstream exhaust catalyst. Pre-ignition and knock detection windows and thresholds may also be adjusted based on the deactivation to improve the efficiency of knock and pre-ignition detection.

The present invention relates to an uneven cylinder displacement arrangement of a multi-stage variable displacement engine. By arranging a plurality of cylinders of at least two different cylinder bores or at least two different strokes in an engine while grouping the plural cylinders into at least two cylinder groups, e.g. grouping odd-numbered cylinders in an ignition sequence of the engine into a first group while grouping even-numbered cylinders in an ignition sequence of the engine into a second group, the engine is enabled to have multi-stage displacement capability adapted to various operation speeds for reducing fuel consumption since the displacement of the engine can be varied by using the ignition sequence to control and select which groups are to be ignited for matching the current load of the engine. In a preferred embodiment of the invention, there are two kinds of cylinders of different cylinder bores arranged in an engine which are grouped into two cylinder groups by the control of the ignition sequence of the engine, whereas the cylinder bore of a cylinder grouped in one of the two cylinder group is the same as another cylinder of the same cylinder group, but is different to those grouped in another cylinder group.

A variable displacement reciprocating pump with pumping rate that is adjustable from zero to maximum stroke while the pump is running. Stroke is varied by changing relative position of pairs of eccentric inner and outer cams that drive the pump's plungers. The pump's input drive shaft drives two gear trains: a first gear train that turns the inner cams and a second gear train that turns the outer cams. These cams normally revolve together with no relative motion occurring between them. A rotary actuator is positioned in the first gear train to rotate the inner cams relative to the outer cams and thereby changes the pump's stroke. A computerized system of sensors and control valves allows the pump to be automatically controlled or limited to any one or combination of desired output flow, pressure and horsepower.

The invention discloses a fracturing method for comprehensively controlling fracture height. The method includes: injecting reversing agent to form an artificial isolating layer, using clean fracturing fluid, controlling construction scale, designing construction pumping programs of variable displacement and low displacement, using a combination of supporting agent with different grain sizes, and adjusting the pumping programs according to construction pressure monitoring results. The fracturing method for comprehensively controlling fracture height is simple in process, convenient to operate, evident in construction effect, capable of being widely used in renovation construction of oil-gas reservoirs with a thin target reservoir stratum and small stress difference between the reservoir stratum and the isolating layer, and capable of well controlling vertical extension of fractures so as to avoid ineffective extension of a communication water layer, a gas layer or in the vertical direction, lower using amount of the fracturing fluid and the supporting agent, reduce cost of fracturing construction and improve effect of fracturing modification yield increase.