Robert Boschgmbh

Gerd Loesch

Sandro Soccol

Bernd Rosenau

Uwe Kuhn

Horst Klinger

Peter Traub

Thomas Goettel

Francois Rossignol

Markus Rueckle

Regis Blanc

Erhard Faix

Andre Fromentoux

Rainer Lorenz

Rainer Haeberer

Josef Guentert

Siegfried Ruthardt

Helmut Clauss

Antonio Diaferia

Peter Grabert

Sandra Ranaldo

Marcel Wuest

Nicola Cimaglia

Mathias Schumacher

Karl-Heinz Linek

Paul Wuetherich

Rosanna Iorizzo

Bernd Roseneau

Giuseppe Palma

Florian Kleer

A radial piston pump has a pump housing containing pump elements and whose high-pressure conduits extending in the pump housing are embodied so as to significantly increase the permissible operating pressures.

Radial piston pump for fuel injection system having improved high-pressure resistance

A fuel injection system has a low-pressure pump for withdrawing fuel from a tank and a high-pressure pump, which is supplied by the low-pressure pump and has camshaft-actuated pump elements. An on-off valve is connected on the inlet side to the pressure side of the low-pressure pump and on the outlet side, is connected on the one hand to a camshaft chamber of the high-pressure pump and on the other hand, is connected to the suction side of the low-pressure pump. At a first pressure threshold, a spring-loaded valve piston of the on-off valve opens a connection between the low-pressure pump and the camshaft chamber and at a relatively higher second pressure threshold, opens a connection between the pressure side and the suction side of the low-pressure pump. A throttle bore in the bottom of the valve piston serves to ventilate the low-pressure system.

On-off valve in a fuel injection system for internal combustion engines

The invention relates to a radial piston pump for high-pressure fuel delivery in fuel injection systems of internal combustion engines, particularly in a common rail injection system. The pump includes a drive shaft that is supported in a pump housing and is embodied eccentrically or has a number of cam-like projections in the circumference direction. A number of pistons that are disposed radially with regard to the drive shaft are each disposed in a respective cylinder chamber and are set into a reciprocating motion in the radial direction in the cylinder chamber upon rotation of the drive shaft. Each respective cylinder chamber is sealed on the radial outside in relation to the drive shaft by a valve plate that has an intake side check valve and a high-pressure side check valve. In order to increase the efficiency of the pump, the intake side check valve has a tappet that passes through the valve plate and this tappet, on an end oriented toward the cylinder chamber has a valve disk that is placed in a sealed fashion against a sealing seat of the valve plate. On a side of the valve plate remote from the cylinder chamber, a device is provided, which pre-stresses the tappet in the closing direction.

Radial piston pump for high-pressure fuel delivery

A common rail system having a regulated prefeed pump, which pumps a fuel flow from a fuel tank to a high-pressure pump. The fuel flow is split with the aid of a valve assembly into a lubricant flow and a high-pressure feed flow that is pumped into a high-pressure reservoir, and acted upon by high pressure. The prefeed pump has a substantially linear characteristic feed curve with a certain slope. To improve the regulating performance, the valve assembly for the lubricant flow includes a valve whose characteristic feed curve initially rises in a first portion (I) with the rpm of the prefeed pump with the same slope as the characteristic feed curve of the prefeed pump. Then in a second portion (II) rises substantially linearly, with a lesser slope than the characteristic feed curve of the prefeed pump, and in a third portion (III) finally drops again.

Common rail system

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.

Piston pump for high pressure fuel supply

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.

Quantity control valve for a fuel injection system

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.

Fuel pump assembly

Fuel injector

The invention relates to a quantity control valve for a fuel injection system, used in internal combustion engines, with a longitudinal slide that is movable in a valve housing between a restoring spring chamber and a 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 in the control chamber is delivered past the longitudinal slide via a throttle or baffle valve. In the closing position, firstly, a cylindrical guide region of the longitudinal slide bounded on both sides by annular grooves blocks off an inlet bore. The guide region is wider than the diameter of the inlet bore. Secondly, it covers an outlet bore except for a partial intersection with the relieved annular groove shifted into the return in the opening direction of the longitudinal slide. By the disposition of the inlet and outlet bores in combination with the contour of the longitudinal slide, a zero quantity feed can be unambiguously represented in the blocking position of the longitudinal slide.

Quantity control valve

Fuel injection system for internal combustion engines

Growing community of inventors

Stuttgart, Germany

Gerd Loesch