A piston pump, in particular a high-pressure fuel pump for an injection system of an internal combustion engine, has a piston and a working chamber which is delimited by the piston. The piston has a running surface section, via which the piston is guided with a guide element, and is configured and developed in such a way that the running surface section of the piston tapers in cross section towards its end which faces the working chamber.

Various embodiments include a method for checking a calibration of a pressure sensor comprising: moving a piston toward a TDC in successive cycles; while the piston moves toward TDC, closing an inlet valve thereby adjusting a setpoint value of a fluid pressure; measuring the fluid pressure with the pressure sensor arranged downstream of the outlet valve; applying a measurement current to the electromagnet when the inlet valve is closed; while the piston moves away from TDC, detecting an opening position of the inlet valve on the basis of a predetermined change with respect to time of the measurement current at which an opening movement of the inlet valve begins; over multiple pump cycles, changing the setpoint value of the fluid pressure by a predetermined difference; checking whether the change in opening position satisfies a predetermined correspondence criterion; and if the criterion is met, generating a fault signal.

A vehicle includes a pump configured to discharge a fuel by reciprocating a plunger, a rail configured to store the fuel discharged from the pump, and a fuel injection valve configured to inject the fuel supplied from the rail. A controller for the vehicle includes a waveform obtaining unit and a phase shift obtaining unit. The waveform obtaining unit is configured to obtain a waveform of a fuel pressure in the rail as a function of time in a predetermined period. The phase shift obtaining unit is configured to obtain a phase shift based on the waveform obtained by the waveform obtaining unit. The phase shift is an offset between a timing the plunger reciprocated in the pump arrives at a first position and a timing a piston reciprocating in an internal combustion engine arrives at a second position.

A method of adaptively predicting, during operation of a pump, a mass of fuel pumped by the pump during a pumping event to a fuel accumulator (“Q.sub.pump”) to control operation of the pump is provided, comprising: generating an adaptive model of operation of the pump, including estimating a start of pumping (“SOP”) position of a plunger of the pump, estimating Q.sub.pump, determining a converged value of the estimated SOP position, and determining a converged value of the estimated Q.sub.pump; using the adaptive model to predict Q.sub.pump by inputting to the model the converged value of the estimated SOP position, a measured pressure of fuel in the fuel accumulator and a measured temperature of fuel in the fuel accumulator; and controlling operation of the pump in response to the predicted Q.sub.pump.

A high pressure fuel pump is provided with a pumping bore and a pressure relief valve only opening to enable a return flow from the outlet conduit back to the compression chamber when the pressure in the outlet conduit exceeds a predetermined threshold. The pressure relief valve is arranged in an elongated pressure relief valve chamber extending parallel and offset to the pumping bore.

A method for monitoring a pressure sensor in a direct injection system including at least one common rail, a high-pressure fuel pump, a hydraulic circuit connecting the high-pressure pump to the common rail, a passive pressure-limiting valve connected to the hydraulic circuit, configured to open once the pressure in the hydraulic circuit is greater than a threshold pressure, so as to discharge the fuel, including the steps of detecting the opening of the pressure-limiting valve, measuring the pressure P.sub.MES corresponding to the time of opening of the pressure-limiting valve and comparing the measured pressure P.sub.MES to the threshold pressure P.sub.1 in order to detect a drift in the pressure sensor.

A control device for controlling an engine provided with a fuel pump including a pressurizing chamber, a plunger inserted into the pressurizing chamber and which changes a volume of the pressurizing chamber, and an on-off valve configured to open and close a suction port, is provided. When a pressurizing cycle consists of a period of pressurizing stroke in which the volume of the pressurizing chamber is reduced to allow fuel to be pressurized and a period of suction stroke in which the volume of the pressurizing chamber is increased to allow fuel to be drawn into the pressurizing chamber, a closing cycle of the on-off valve is controlled so that a ratio of the closing cycle to the pressurizing cycle becomes smaller in a second combustion mode where a partial compression-ignition combustion is performed than in a first combustion mode where SI combustion is performed.

A direct injection assembly includes a follower mechanism having an input piston operably engaged with a camshaft and moving between first and second input positions along a first follower axis, in response to the camshaft rotating about a camshaft axis. The follower mechanism further includes an output piston movable between first and second output positions along a second follower axis. The follower mechanism further includes a coupler mechanism movable between a deactivated state and an activated state where the coupler mechanism holds the input piston and the output piston in fixed positions relative to one another, such that the coupler mechanism transmits a force from the input piston to the output piston. A pump includes a plunger movable from a first plunger position to a second plunger position where the plunger pressurizes the volume of fuel, in response to the plunger receiving the force from the output piston.

The error diagnosis device has: an input unit that receives detected values for pressure inside the common rail; a calculation unit that, if the detected values are less than a target common rail pressure, calculates the pressure differences and the fuel pump discharge amounts, and a determination unit that determines whether or not a set time has lapsed in a slate in which the pressure differences are at least a first threshold value and less than a second threshold value and the discharge amounts are at least a third threshold value and less than a fourth threshold value. The determination unit determines that an error has occurred in the high-pressure pump if the set time has lapsed and determines that an error has occurred in the flowrate adjustment valve if the set time has not lapsed.

Disclosed are a high pressure fuel pump and a liquid petroleum direct injection system including the same. The high pressure fuel pump includes a body having an intake port and an exhaust port, and provided therein with a pressing device configured to press a portion of fuel at a high pressure, a spill valve coupled to one side of the body to control a supply flow rate and exhaust pressure of the fuel, and a cover coupled to an upper portion of the body and having a recovery port for recovering a portion of the fuel to a bombe. The cover has a dome shape that is convex upward. The cover collects gaseous fuel generated by heat of an engine when the engine is turned off after driving, that is, collects vapor to recover the vapor to the bombe, thereby improving the restartability.