DE102008009226A1 - High-pressure pump for fuel injection, has housing and base body which is formed from flange part connected with housing and consisting of guide component - Google Patents

Abstract

The high-pressure pump has a housing (1) and a base body which is formed from a flange part (2A) connected with the housing and consisting of a guide component (2B). A suction valve (V1) and high pressure valve (V2) are provided which are provided in the flange part of the base body. A piston (3) passes through the guide component of the base body and a fluid supply channel is formed in the flange part of the base body. The longitudinal axes of the suction and high pressure valves are perpendicular to the longitudinal axis of the base body.

Description

The The invention relates to high-pressure pumps, in particular for fuel injection.

• 1. Die großen Außenmaße der Konstruktionen: der Schwerpunkt von der Pumpeneinheit befindet sich weit fern von der Nockenwelle, weil das Saugventil perpendikular zum Hochdruckventil ist, und der Grundkörper unsymmetrisch ist.
• 2. Teuerung des Grundkörpers wegen unsymmetrischer Anordnung der Ventile bezüglich des Kolbens; besonders schwer bei der Fertigung ist der Eingangsbereich der Bohrung vom Hochdruckventil (herstellbar nur durch Elektroerodieren).
• 3. Großer Todraum, der aus 3 Räumen besteht (siehe, gegebenenfalls, die Zeichnungen benannten Patents): der Erste befindet sich um der Seitenfläche vom oberen Teil des Kolbens, der Zweite – zwischen dem ersten Raum und dem Hochdruckventil, der Dritte – zwischen der Kolbenstirnseite und dem Saugventil (in OT). Der erste Raum dient für Umfluß des Fluids um den Kolben beim Fluidfluß zum zweiten Raum, der Zweite ist der größte, weil es notwendig ist, die Ventile voneinander zu entfernen wegen stark unregelmäßiger Kräfteverteilung im dünnen Zwischenbereich von den Ventilen, der Dritte dient dafür, Hubbewegung des Saugventils zuzulassen.
• 4. Große Verluste auf Fluidreibung und die Kavitation im ersten Raum, weil wirbelartige Fluidströme bei sehr enger Spalte (in den Boschserienpumpen = 0.25 mm) mit großer Fluidreibung an den Wänden des ersten Todraums stattfinden.

Their closer constructions are the designs created by company "Bosch" from the period beginning in 2004, based on an overall concept of the high-pressure pump (see, for example, US Pat. DE 10 2004 013 244 ). These constructions have the following disadvantages:

• 1. The large external dimensions of the constructions: the center of gravity of the pump unit is far away from the camshaft because the suction valve is perpendicular to the high pressure valve and the body is asymmetrical.
• 2. Inflation of the main body because of asymmetrical arrangement of the valves with respect to the piston; Particularly difficult in the production of the input area of the bore of the high pressure valve (can be produced only by electroerodating).
• 3. Big dead space consisting of 3 rooms (see, if necessary, the drawings of the named patent): the first is around the side surface of the upper part of the piston, the second - between the first space and the high pressure valve, the third - between the Piston end and the suction valve (in TDC). The first space serves to circulate the fluid around the piston in the fluid flow to the second space, the second is the largest, because it is necessary to remove the valves from each other because of highly irregular distribution of forces in the thin intermediate region of the valves, the third serves for stroke movement allow the suction valve.
• 4. Large losses of fluid friction and cavitation in the first space, because vortex-like fluid flows occur with very narrow gaps (in the Bosch series pumps = 0.25 mm) with high fluid friction on the walls of the first dead space.

• – ein Gehäuse,
• – einen Grundkörper, der aus einem mit dem Gehäuse kontaktierten Flanschteil und einem Führungsteil besteht,
• – ein Saug- und ein Hochdruckventil, die sich im Flanschteil des Grundkörpers befinden,
• – einen Kolben, der im Führungsteil des Grundkörpers durchgeht, wobei im Flanschteil des Grundkörpers ein Fluidzufuhrkanal ausgebildet ist, der den Fluidzufuhrkanal im Gehäuse mit dem Einlasskanal des Saugventils verbindet, und dadurch gekennzeichnet, dass die Längsachsen der Saug- und Hochdruckventile der Längsachse vom Grundkörper senkrecht sind.

The object of the proposed invention is to provide a concept of high pressure pumps free of named disadvantages. This goal is achieved by the fact that the high-pressure pump includes the following units:

• A housing,
• A base body consisting of a flange part contacted with the housing and a guide part,
• A suction and a high pressure valve located in the flange portion of the body,
• - A piston which passes in the guide part of the body, wherein in the flange part of the body, a fluid supply channel is formed, which connects the fluid supply channel in the housing with the inlet channel of the suction valve, and characterized in that the longitudinal axes of the suction and high pressure valves of the longitudinal axis of the main body perpendicular are.

Of the Fluid supply channel in the main body can both in the plane, in which valves are located as well as perpendicular to this plane be.

The Longitudinal axes of the suction and high pressure valves can coincide - in this case, the construction is easier for manufacturing, but its profitability is lower, because for their operation a small space (he can as a Todraum) is necessary at the high pressure valve. If those Long axes do not coincide, there is no need for this room.

It It is recommended that the suction and high pressure valves in an annular Block in the housing to accommodate - thus can one their sites for the valves cheaper make.

On the 1 and 2 Examples of realization of proposed invention are shown

on 1 : the longitudinal axes of the suction and high pressure valves do not coincide,

on 2 : they collapse, the valves are housed in the block of a housing.

On the pictures are:

D

of the Pressure chamber;

1

the Casing;

2A

of the Flange part of the main body;

2 B

of the Guide part of the body;

3

of the Piston;

V1

the suction valve;

V2

the High-pressure valve;

F1

of the Supply channel in the housing;

F2

of the Supply channel in the main body;

F3

of the Inlet channel of the suction valve;

B

of the Valve block.

The High pressure pumps manufactured according to the proposed invention should have high efficiency - because of small Dead space and minimal losses on fluid friction (low vortex Fluid flows and there are no fluid flows in close Column) and are easy to produce because of symmetrical arrangement the valves that are just removed from the camshaft.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102004013244 [0002]

Claims (3)

High pressure pump includes - a housing, - a main body, which consists of a contacted with the housing flange and a guide part, - a suction and a high pressure valve, which are located in the flange part of the body, - a piston which passes in the guide part of the body, wherein in the flange portion of the base body, a fluid supply channel is formed, which connects the fluid supply channel in the housing with the inlet channel of the suction valve, and characterized in that the longitudinal axes of the suction and high pressure valves of the longitudinal axis of the main body (approximately) are perpendicular. High pressure pump according to claim 2, characterized that the longitudinal axes of the suction and high pressure valves coincide. High-pressure pump according to claim 1 or 2, characterized that the suction and high pressure valves in an annular Block are housed in the housing.