摘要:
A hydraulically controlled actuator for actuation of an exhaust-side gas exchange valve of an internal combustion engine, containing a control piston that is displaceable within a cylinder and, with piston sides facing away from one another, delimits pressure chambers, of which the one pressure chamber impinges upon the gas exchange valve in the closing direction and the other pressure chamber impinges upon the gas exchange valve in the opening direction. In the actuator is provided at least one spring element, which can be brought into a preloaded state by the control piston moving in the closing direction of the gas exchange valve, and whose stored potential energy accelerates the gas exchange valve in the opening direction at least at the beginning of an opening phase, is provided. This results in a reduction in the energy expended in the context of valve actuation.
摘要:
An apparatus for controlling gas exchange valves includes at least one valve positioner, associated with a gas exchange valve, and a pressure supply device which supplies the valve positioner with a fluid under high pressure. The valve positioner encompasses a working cylinder having a positioning piston, coupled to the gas exchange valve, which delimits an upper pressure space for opening the valve and a lower pressure space for closing the valve, and encompasses a control valve controlling the hydraulic pressure in the pressure spaces. In order to reduce the manufacturing costs and electrical energy demand of the apparatus, the upper pressure space is connected directly, and the lower pressure space via a restrictor throttle, to the pressure supply device; and the control valve is connected to the lower pressure space and to a relief line. Depending on the switch position, the control valve additionally connects the lower pressure space to the relief line or blocks it off from the relief line.
摘要:
A control system and a control method for an internal combustion engine have a cylinder including an intake valve and an exhaust valve with a fully variable valve-gear assembly. An engine control unit determines setpoint values with regard to a fresh gas charge, an internal residual gas charge, a torque reduction, an EGR control strategy, and a charging strategy. In addition, a transmission device is provided which transmits setpoint values determined by the engine control unit to a valve control unit in synchronization with the crankshaft angle. The valve control unit controls the fully variable valve-gear assembly of the intake and exhaust valve of the cylinder of the internal combustion engine on the basis of the setpoint values determined by the engine control unit.
摘要:
The invention relates to a device of the build-up of pressure in supply systems (6, 11, 20, and 23) to components (19, 36) on internal combustion engines (2). The invention includes directly couples lubricant systems and pressure-generating systems (3, 8), an electric fuel pump (34), as well as a control apparatus for determining lubricant pressures. A supply module (12, 34) is provided with an independent drive (16) and supplies lubricant in the lubricant oil circuit (24) or to selected lubricating position, or fuel into a fuel supply (36). The supply module (12, 34) can optionally include a pressure converter (30).
摘要:
A piston pump of the roller tappet type for high-pressure fuel delivery in fuel injection systems of internal combustion engines, particularly in common rail injection systems. A drive shaft that is supported in the pump housing and has a number of cam-like projections in the circumference direction. At least one tappet that is disposed in a cylinder chamber radially with regard to the drive shaft and in its radially inner end region has a rotatable roller which is supported so that it can roll in the circumference direction against the drive shaft in the region of its projections in order to reduce the wear in the region of the roller bearing. The pump is embodied so that a lubricant supply opening that leads from the circumference of the tappet and feeds into the radially inner tappet end region supporting the roller and at least during a part of the stroke, communicates with a lubricant supply line of the housing, which line feeds into the cylinder chamber.
摘要:
The invention relates to a quantity control valve for a fuel injection system, used in internal combustion engines, which includes a longitudinal slide that is movable in a valve housing between a first and a second control chamber and that allocates the fuel, flowing in from at least one low-pressure pump, to at least one high-pressure pump. For driving the longitudinal slide, the inflowing fuel is delivered into the first control chamber via a throttle or baffle valve, past the longitudinal slide. In the second control chamber, there is either a restoring spring that urges the longitudinal slide in the direction of its closing position, or the longitudinal slide there has an effective face-end surface area upstream of which a control line containing a throttle valve ends; this end face is smaller in surface area than the effective surface area of the face end in the first control chamber. In the closing position, the longitudinal slide blocks off the outlet bore with one of its cylindrical guide portions, while with regard to the inlet bore it has a narrowed region, which opposite the longitudinal slide bore leaves a flow cross section open that changes gradually to zero in the direction of the guide portion. In the valve, the flow of fuel is controlled by a targeted manipulation of a cross section via a long slide stroke.
摘要:
The invention relates to a fuel pump assembly having a low-pressure region (ND) with at least one low-pressure pump-and a high-pressure region (HD) with at least one regulated-quantity high-pressure pump, which pumps a quantity of fuel required to compensate for the quantitative balance in the high-pressure region, the quantity regulation being effected via a metering unit which is disposed between the low-pressure pump and the high-pressure pump. In order, by simple and sturdy means with high availability and a long service life, to prevent the fuel quantity in correctly pumped by the metering unit at certain operating points from reaching the high-pressure region, the invention proposes that the pumping flow of the low-pressure pump is greater than the pumping flow of the high-pressure pump; that a fuel return line branches off between the metering unit and the high-pressure pump and discharges into the inlet of the low-pressure pump; and that a control element is disposed in the return line.
摘要:
A fuel injection system for internal combustion engines, having a high-pressure pump, whose pump work chamber can be made to communicate on the intake side with a fuel tank via a supply line and on the compression side with a common rail via a high-pressure line, from which common rail a plurality of injection lines lead away to the individual injection valves, and having one pressure valve each in the supply line and the high-pressure line, by way of which a return flow of fuel out of the pump work chamber into the supply line and out of the high-pressure line into the pump work chamber is prevented. The pressure valve of the supply line and the pressure valve of the high-pressure line are disposed in a common valve combination.
摘要:
A method for controlling the opening of at least one intake valve of a combustion chamber in a periodically working piston engine, at least one intake valve of the combustion chamber being opened during a first partial period of a working period of the piston engine for charging the combustion chamber; and at least one intake valve of the combustion chamber being opened during a second partial period of the working period, wherein the second partial period begins after the combustion of the combustion chamber charge and has no overlap with the first partial period.
摘要:
Disclosed is a simple, easy-to-produce, and reliable connection between a shaft of a gas exchange valve and an actuator. This connection is detachable and, as a result, can be connected and disconnected multiple times. It is also possible to dispose the coupling piece on the shaft of the gas exchange valve and provide circumferential grooves on the control element of the actuator.