Scania Cv Ab

Scania Cv Ab (publ)

Kim Kylström

Roger Hälleberg

Ola Stenlåås

Ulf Carlsson

Peter Sperle

Vesa Hokkanen

Dan Cedfors

Jens Svensson

Patrik Fogelberg

Anders Jonsson

Tomas Flink

Peter Gustafsson

Carina Forsberg

Adam Berg

Mats Hägg

Alex Elofsson Alenius

Johannes Dahl

The invention relates to a method for operating a fuel supply pump of a vehicle, the vehicle comprising a combustion engine system and a gearbox, the method comprising the steps of: determining one or more operational values of at least one operational parameter of the combustion engine system; determining a reduction of a fuel provision rate to the combustion engine system; determining whether a gear step change of the gearbox is at hand, on the basis of the determined one or more operational values of the at least one operational parameter; and in case a gear step change of the gearbox is at hand, controlling operation of the fuel supply pump so as to maintain fuel supply pump speed.

System and method for operating a fuel supply pump of a vehicle

The present invention relates to a high pressure fuel pump comprising an inlet channel in connection with a first chamber, through which inlet channel fuel is led to the first chamber, a second chamber arranged in connection with the first chamber, an outlet valve arranged in connection with the second chamber and an inlet valve comprising a piston, with a first end section and a second end section. The piston is moveably arranged with the first end section in a third chamber, and the second end section is moveably arranged between the first chamber and the second chamber. A press element is arranged to act on the piston with a mechanic force, so that the piston strives to be positioned with the second end section closing the connection between the first chamber and the second chamber. The inlet valve is in a closed state and may be controlled via an electromagnetic unit.

High pressure fuel pump for a fuel system

Provided is a method for diagnosing unintended fuelling from one or more fuel injectors of a multi cylinder internal combustion engine during engine operation. Pressurized fuel is intended to be distributed by means of said fuel injectors from said accumulator tank to the cylinders for combustion. An oxidation catalyst is arranged downstream said cylinders. The method comprises: determining the pressure in the fuel accumulator tank and whether said pressure is decreasing; and determining whether the actual amount of fuel provided by the pump unit exceeds the demanded amount of fuel. The method further comprises the steps of: determining whether the temperature associated with the oxidation catalyst is above a certain level and/or determining whether the air/fuel ratio is below a certain level and/or determining whether an amount of particulate matter is above a certain level; and confirming an unintended fuelling based on the determined conditions.

Method and system for diagnosing unintended fuelling from fuel injectors of an engine

A method and a system for control of a low-pressure circuit in a fuel system of a vehicle, which circuit is arranged to provide the vehicle's engine with fuel from at least one fuel tank via a pressure change system. The system includes a determination unit to make a determination of a future working point for the engine. The determination unit bases this determination on information about a section of road ahead. The system also has a pump operating unit which operates at least one controllable fuel pump which is part of the low-pressure circuit. The pump operating unit bases this operation on the future working point.

Method for controlling a low pressure circuit by employing future conditions

A valve (') for a fuel system for a combustion engine: A ball retainer () is provided with a cavity () to accommodate a ball (). The ball () has a first seal surface () to cooperate with and abut sealingly against a seat (). The ball retainer () has a secondary seal surface () to cooperate with and abut sealingly against the seat () when the ball () is not in the ball retainer (). Also, a method for controlling a fuel system for a combustion engine.

Valve for a fuel system for a combustion engine and method for controlling a fuel system for a combustion engine

A method for determination of the bulk modulus of fuels in a fuel system of a combustion engine () with a common rail injection system (), with a high pressure volume () including the high pressure side of a high pressure pump () and a fuel accumulator () with injectors () for injection of fuel into the cylinders of the combustion engine. The method including: first determining the volume of the high pressure volume by supplying a fuel with a known bulk modulus to the fuel system and by controlling the high pressure pump () so that it performs a pump stroke with the volume of the high pressure volume closed. The value of the determined volume is later used with another fuel in order to determine the latter fuel's bulk modulus.

Method for determining the bulk modulus of fuels

In a high pressure pump in a system for fuel injection in a combustion engine, determining whether a predetermined partial load operating condition prevails in the combustion engine, at which one single of several pump elements () in the high pressure pump is capable of alone delivering a fuel pressure requested in an accumulator tank (), according to a first reference value, and to achieve a reproducible increase of the fuel pressure to a second reference value. If applicable, the high pressure pump's pump elements are controlled so that one single pump element alone delivers the fuel pressure in the accumulator tank according to the first reference value, whereupon this reference value is changed to the second reference value, and the actual development of the pressure in the accumulator tank as a function of time is determined, and compared with stored values of similar developments for the determination of information regarding the pump element's performance ability.

Method and device for operation of a high pressure fuel pump

A method for function control of a high pressure pump () in a system for fuel injection in a combustion engine: The method is carried out during stationary operating conditions in the combustion engine, with a constantly requested reference value for the fuel pressure in an accumulator tank (). A feeding pump () in a low pressure part () of the system is controlled so that the fuel pressure in the low pressure part at the inlet to the high pressure pump falls, and at the same time this fuel pressure is measured, as is the fuel pressure in the accumulator tank. The development of the measured fuel pressure in the accumulator tank is compared to the reference value during the pressure reduction in the low pressure part, for the generation of information about the high pressure pump's functionality.

Method and device for functional control of a high pressure fuel pump

An injection unit () for injection of a first fuel (f) and a second fuel (f) in a combustion space. The injection unit () receives the first fuel (f) from a fuel source () at a high pressure, and a second fuel (f) from a second fuel source () at a lower pressure, an actuator () initiates a process of injecting at least the second fuel (f) in the combustion space, and an injection nozzle () injects at least the second fuel (f) in the combustion space. The injection unit includes a pressure boosting device () for increasing the pressure of the second fuel (f) higher than the pressure in the second fuel source () by means of the pressure of the first fuel (f), before the second fuel is injected.

Injection unit for injection of a first fuel and a second fuel in a combustion space

A fuel system for injection of a fuel mixture in a combustion engine includes an inlet circuit () leading fuel to the engine (). The inlet circuit () includes a feed pump (), a high-pressure pump (), an accumulator tank (), and at least one injection unit () injecting fuel in a combustion space of the engine (). The inlet circuit () includes a space () for receiving a first fuel () from a first fuel source () and a second fuel () from a second fuel source (). A mixing device () mixes to the first fuel () and the second fuel () resulting in a substantially uniform fuel mixture which the injection unit () injects into the engine's combustion space.

Fuel system for injection of a fuel mixture in a combustion engine

A fuel pump and a method for controlling a fuel pump. At least two pumps run at a mutual phase displacement such that they are able to receive fuel during different periods of time. A control unit causes a valve, which is only settable in an open position and a closed position, to lead a desired amount of fuel to the respective pump. The control unit places the valve in the open position for a variable portion of the periods so that an individually controlled amount of fuel is led to the respective pump during those periods. Maintenance of good efficiency of the fuel pump and low noise emissions is thus made possible in operating situations where the fuel pump delivers a reduced amount of fuel.

Fuel pump and a method for controlling a fuel pump

An injector for fuel includes a passage for receiving fuel at an above-atmospheric first pressure, a pressure amplifier and an injection valve which is settable in an open position and a closed position. The injection valve includes a piston element, a closing chamber and an opening chamber. To inject fuel, the pressure amplifier generates a higher second fuel pressure in the opening chamber so that the valve element moves towards an open position and fuel is injected. To end injection of fuel, the high pressure in the opening chamber is reduced and the closing chamber is connected to the fuel source at the first pressure so that the valve is moved towards the closed position by a combined force created by the first pressure and the spring.

Growing community of inventors

Tullinge, Sweden

Kim Kylström