DE102014206968A1 - High pressure pump and high pressure directional valve - Google Patents

Abstract

A high-pressure directional valve (2) of a high-pressure pump (1) of a fuel injection system for air-compressing, self-igniting internal combustion engines comprises a valve chamber (22) delimited by a valve wall (21), a valve closing body (40) arranged in the valve chamber (22) and one on the valve wall (21) formed valve seat surface (41) acts together to form a sealing seat, and a spring element (30) which acts on the valve seat body (40) along a valve axis (27) against the valve seat surface (41). Here, the valve closing body (40) is formed on a calotte head (24) of a dome (23). The calotte (23) has a calotte body (25) connected to the calotte head (24). Furthermore, the dome (23) is guided on its calotte body (25) on the valve wall (21) along the valve axis (27). On the calotte body (25) lateral recesses (43, 44) are provided, which are configured so that between the calotte body (25) and the valve wall (21) fuel passages (45, 46) are formed, which a fuel flow from the sealing seat ( 42) to one of the cap head (24) facing away from Kalottenfuß (26) allow the dome (23).

Description

State of the art

The invention relates to a high-pressure pump, in particular a radial or in-line piston pump for fuel injection systems of air-compressing, self-igniting internal combustion engines. Furthermore, the invention relates to a high-pressure directional valve for a component of a fuel injection system, in particular for such a high-pressure pump.

From the DE 10 2009 003 054 A1 a high-pressure pump is known which is used for fuel injection systems of air-compressing, self-igniting internal combustion engines. The known high-pressure pump has a pump assembly and a drive shaft which serves to drive the pump assembly. In this case, the pump assembly has a piston which delimits a pump working chamber in a cylinder bore. Fuel can be introduced from a fuel channel into the pump working chamber via an inlet valve. Furthermore, an outlet valve is provided on a housing part, can be guided via the high-pressure fuel from the pump working chamber to a fuel channel, which may be connected, for example, with a common rail to lead under high pressure fuel to the common rail.

In a high pressure pump, as they are from the DE 10 2009 003 054 A1 is known, it is conceivable to carry out the outlet valve for the pump working space as a high-pressure directional valve, which has a spring-loaded cap. As a result, when the fuel is compressed in the pump working chamber, a valve interface to the common rail can be formed by the piston. If the pressure in the pump chamber is greater than the pressure in the common rail, then the exhaust valve opens. If the pressure in the pump working chamber falls below the pressure in the common rail, the exhaust valve closes again. Such a valve with dome may be drilled axially hollow and have a plurality of radial bores in the flow direction behind a seating area. In such a conceivable embodiment of the fuel then flows through the Kalottendichtsitz by radial holes in an axial Kalottenbohrung and further via a spring holder to the common rail. However, such a conceivable embodiment has the disadvantage that the manufacture of the calotte is very expensive. In particular, several holes must be introduced into the calotte, which additionally result in one or more bore overlaps in the interior of the calotte.

Disclosure of the invention

The high-pressure directional valve according to the invention with the features of claim 1 and the high-pressure pump according to the invention with the features of claim 10 have the advantage that an improved embodiment is made possible. In particular, high functionality of the high-pressure directional valve or of the high-pressure directional valve serving as an outlet valve can be achieved with comparatively low production costs. This may result in further benefits.

The measures listed in the dependent claims advantageous refinements of the specified in claim 1 high-pressure directional valve and the high-pressure pump specified in claim 10 are possible.

The dome of the high-pressure directional valve can be machined in a simplified manner and thus manufactured at a reduced cost. This hole intersections, which are particularly problematic inside the dome, can be avoided. Furthermore, manufacturing steps for deburring holes can be reduced or eliminated altogether. This also reduces the occurrence of particles in the high pressure area. In addition, the production costs can be correspondingly reduced by simplified and reduced processing steps. Due to the robust design and possible adaptations to the application, in particular a possible mass reduction of the dome, also results in a wide range of applications. In particular, the high-pressure directional valve according to the invention can be used in a possibly correspondingly adapted embodiment in a multiplicity of common rail fuel injection systems.

The calotte of the high-pressure directional valve advantageously has a calotte head, a calotte body and a calotte foot. The sealing function is realized here on the calotte head. When the high-pressure directional valve is open, the fuel flows from the calotte head laterally past the calotte body to the dome foot. For this purpose, the calotte body has at least one lateral recess. Preferably, a plurality of lateral recesses are provided. If a plurality of lateral recesses are provided, then these are preferably configured correspondingly to one another and are distributed uniformly with respect to the valve axis on the calotte body.

It is advantageous that at least one lateral recess is designed as a lateral flattening. In this case, it is also advantageous that such a lateral flattening is designed as at least substantially flat and / or at least substantially rectangular lateral flattening. This also allows a constant flow cross section between the valve body and the valve wall can be realized at the fuel passage along the valve axis. This results in an advantageous flow behavior.

It is also advantageous that at the Kalottenfuß a support surface and a retaining ring are formed, that the retaining ring surrounds the support surface in sections, that the spring element is supported on the support surface of the Kalottenfußes and that the retaining ring has at least one interruption of the fuel passage between the lateral recess of the calotte body and the valve wall leads to an axial fuel channel. Here, it is also advantageous that a spring holder is provided, on which the spring is supported, and that the axial fuel channel leads axially through the spring holder. About the interruption thus enters the fuel from the fuel passage between the lateral recess of the calotte body and the valve wall in the axial fuel passage of the spring holder. In particular, thus, the fuel can be guided in the vicinity of the valve axis by the spring holder. Here, an advantageous attachment of the spring holder in the valve chamber is possible. In particular, the spring holder can be pressed.

It is also advantageous here that the interruption of the retaining ring is geometrically associated with the lateral recess of the calotte body. This results in advantageous flow conditions when flowing through the valve chamber, when the sealing seat between the valve closing body and the valve seat surface is opened.

The interruption of the retaining ring can be configured in this case advantageously as a groove-shaped interruption. As a result, a sufficiently large opening cross-section can be realized.

It is also advantageous that the calotte head has an outer cross-section which lies in a projection along the valve axis within an outer cross-section of the calotte body. In this way, when the sealing seat is open, the fuel can advantageously flow between the calotte head and the valve wall to the fuel passage between the calotte body and the valve wall. As a result, the design of the valve chamber can be simplified. Specifically, the valve space can be realized substantially by a bore, at the end of which, for example, a conical valve seat surface is configured.

The dome can be adapted to the particular application in an advantageous manner. Such adjustments can be made in such a way that the flow conditions are not adversely affected. For example, the mass of the dome can be reduced in a suitable manner, if this is sensible or necessary in the particular application. In this case, the dome may advantageously have an axial recess which extends from the Kalottenfuß at least partially through the calotte body. The dome may also advantageously have an axial recess which extends from the Kalottenfuß at least through the Kalottenkörper and optionally in sections through the Kalottenkopf. Depending on the extent of such an axial recess along the valve axis through the calotte and a cross section, in particular diameter, of the axial recess thus results in a mass reduction. The axial recess can be configured in particular advantageously as a bore or stepped bore.

The calotte body may advantageously be based on a cylindrical configuration, wherein the lateral recesses are provided. In this way, an advantageous guidance of the calotte can be realized on the calotte body with respect to the partially cylindrical jacket-shaped valve wall. Advantageously, in this case, the Kalottenkörper have at least two correspondingly configured lateral recesses which are opposite to each other with respect to the valve axis. However, other embodiments of the Kalottenkörpers and the valve wall, with which the Kalottenkörper acts to guide together conceivable.

Brief description of the drawings

Preferred embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawings, in which corresponding elements are provided with corresponding reference numerals. Show it:

1 a high-pressure pump with a high-pressure directional valve in a partial, schematic sectional view according to a first embodiment of the invention;

2 a dome of the in 1 illustrated high-pressure directional valve according to the first embodiment in a schematic, partially sectional view;

3 in the 2 illustrated calotte according to the first embodiment in a schematic representation of the in 2 with III designated direction and

4 in the 2 shown dome of a high-pressure directional valve in a schematic, partially sectional view according to a second embodiment of the invention.

Embodiments of the invention

1 shows a high pressure pump 1 with a high pressure directional valve 2 in a partial, schematic sectional view according to a first embodiment. The high pressure pump 1 can be configured in particular as a radial or inline piston pump. Specifically, the high pressure pump is suitable 1 as a fuel pump for fuel injection systems of air-compressing, self-igniting internal combustion engines. A preferred use of the high-pressure pump 1 consists of a fuel injection system with a fuel rail, a so-called common rail that stores diesel fuel under high pressure. The high-pressure pump according to the invention 1 However, it is also suitable for other applications. The high pressure directional valve 2 The invention is particularly suitable for such a high-pressure pump 1 , However, the high pressure directional valve is suitable 2 The invention also for other components of a fuel injection system, which are used in particular for air-compressing, self-igniting internal combustion engines.

The high pressure pump 1 has a housing part 3 on, on which a fuel connection 4 is designed. Furthermore, on the housing part 3 an approach 5 designed, through which a piston bore 6 extends. The high pressure pump 1 in this case has at least one pump assembly 7 on, which is a pump piston 8th includes. A front page 9 of the pump piston 8th limited here in the piston bore 6 a pump workroom 10 the pump assembly 7 ,

The high pressure pump 1 also has a drive shaft 15 with a cam 16 on. About the cam 16 is the pump piston 8th the pump assembly 7 drivable, as indicated schematically by a double arrow 17 is illustrated. About the associated reciprocating motion of the pump piston 8th alternately gets fuel into the pump work space 10 sucked and then conveyed under high pressure.

To convey the fuel across the pump workspace 10 gets fuel from a connection point 18 via a hydraulic or electro-hydraulic element 19 , for example, as a metering unit 19 or check valve 19 is configured into the pump work space 10 guided. In the compressed state, the fuel under high pressure in a fuel channel 20 promoted through the housing part 3 to the high pressure directional valve 2 extends.

The high pressure directional valve 2 has one of a valve wall 21 limited valve space 22 on. In the valve room 22 is a dome 23 arranged. The dome 23 includes a calotte head 24 , a calotte body 25 and a dome foot 26 , The dome 23 is here along a valve axis 27 aligned. The valve room 22 is rotationally symmetric with respect to the valve axis 27 designed.

Furthermore, the high-pressure directional valve has 2 a penholder 28 up in the valve room 22 is arranged. Here is the pen 28 in a suitable manner in the valve chamber 22 inserted, the spring holder 28 stationary with respect to the housing part 3 is attached. For example, the pen holder 28 in the housing part 3 be pressed. The penholder 28 is also with respect to the valve axis 27 aligned.

A feather 30 of the high-pressure directional valve 2 is between the calotte 23 and the penholder 28 in the valve room 22 arranged. Here is the spring 30 along the valve axis 27 aligned. The feather 30 this extends in sections into a part 31 a stepped bore 32 of the spring holder 28 , The stepped bore 32 forms an axial fuel channel 32 that passes axially through the spring holder 28 leads.

Furthermore, the spring extends 30 partly in a recording 33 of the calf's foot 26 the dome 23 , The feather 30 relies on a supporting surface 34 of the calf's foot 26 from. The dome foot 26 also has a retaining ring 35 on top of the support surface 34 partially encloses. This is the spring 30 reliable in the recording 33 the dome 23 held.

At the calotte head 24 the dome 23 is a valve closing body 40 educated. Furthermore, on the valve wall 21 in the area of the valve closing body 40 a valve seat surface 41 educated. The valve seat area 41 is in this embodiment as a conical valve seat surface 41 designed. The valve closing body 40 the dome 23 works with the on the valve wall 21 trained valve seat surface 41 to a sealing seat 42 together. This acts as a spring 30 trained spring element 30 the valve closing body 40 along the valve axis 27 against the valve seat surface 41 ,

In this embodiment, the dome 23 designed in one piece. Thus, the calotte head 24 with the calotte body 25 connected. Furthermore, the calotte foot 26 with the calotte body 25 connected. During a movement of the calotte head 24 along the valve axis 27 is over the calotte body 25 a guide on the valve wall 21 along the valve axis 27 guaranteed. About the design and bias of the spring 30 is this Opening and closing behavior of the high-pressure directional valve 2 preset and set. If pressure of fuel in a fuel channel 20 is correspondingly large, then the Kalottenkopf 24 subjected to a sufficiently large opening force, the closing force of the spring 30 exceeds. This causes the sealing seat to open 42 so that fuel from the fuel channel 20 in the valve room 22 flows.

In this embodiment, on the calotte body 25 lateral recesses 43 . 44 intended. The lateral recesses 43 . 44 are in this embodiment as lateral flattening 43 . 44 designed. The lateral flattenings 43 . 44 are flat and rectangular in shape. As a result, in the area of lateral flattening 43 . 44 between the calotte body 25 and the valve wall 21 Fuel passages 45 . 46 educated. About the fuel passages 45 . 46 is the fuel flow from the sealing seat 42 to that of the calotte head 24 facing away from Kalottenfuß 26 the dome 23 allows.

The embodiment of the high-pressure directional valve 2 is also referred to below with reference to the 2 and 3 further described.

2 shows the calotte 23 of in 1 illustrated high-pressure directional valve 2 according to the first embodiment in a schematic, partially sectioned illustration. 3 shows the in 2 illustrated calotte 23 according to the first embodiment in a schematic representation of the in 2 with III designated viewing direction. The course of the cylinder jacket-shaped valve wall 21 is here in the 3 illustrated by a broken line.

In this embodiment is on the calotte foot 26 a groove 47 provided by the retaining ring 35 extends. As a result, in the retaining ring 35 grooved breaks 48 . 49 educated. About the groove-shaped interruption 48 Fuel from fuel passage can 45 that between the lateral flattening 43 and the valve wall 21 is formed in the field of recording 33 at the dome foot 26 flow. Accordingly, the fuel from the fuel passage 46 that between the lateral flattening 44 of the calf body 25 and the valve wall 21 is formed, via the groove-shaped interruption 49 of the retaining ring 35 in the field of recording 33 at the dome foot 26 flow. From the field of recording 33 at the dome foot 26 The fuel also passes through the stepped bore 32 formed fuel channel 32 of the spring holder 28 , Thus, with the seal seat open 42 the fuel to an exit 50 of the fuel connection 4 reach.

The interruptions 48 . 49 of the retaining ring 35 are geometrically the lateral flattenings 43 . 44 of the calf body 25 assigned. This results in favorable flow conditions. In the embodiment of the Kalottenkörpers 25 is at least a lateral recess 43 . 44 intended. By the opposite arrangement of the side recesses 43 . 44 The first embodiment results in a pressure balance during operation. Here, the cross sections add up 45 . 46 the fuel passages 45 . 46 in the 3 with respect to the valve wall interrupted 21 are illustrated. The cross sections 45 . 46 the fuel passages 45 . 46 are preferably at least twice as large as a cross section of the opened sealing seat 42 ,

Through the spring guide on the calotte foot 26 and on the penholder 28 is a tilting or buckling of the spring 30 reliably prevented. In this area is the resulting cross-section, in particular by the groove-shaped interruptions 48 . 49 is possible, preferably also at least twice as large as the cross section of the open sealing seat 42 to get a favorable fuel flow from the fuel passages 45 . 46 in the axial fuel channel 32 to enable.

The guide of the calotte body 25 on the cylinder jacket-shaped valve wall 21 takes place on the remaining part-cylinder shell-shaped guide surfaces 51 . 52 of the calf body 25 ,

An outer cross section 55 of the calotte head 24 lies in a projection along the valve axis 27 within an outer cross-section 56 of the calf body 25 , As a result, the fuel flow becomes laterally on the calotte head 24 passed by. Thus, a cost-effective design of the dome 23 possible. Depending on the application, this can also be a multi-part design of the dome 23 be provided.

4 shows the in 2 illustrated calotte 23 a high pressure directional valve 2 in a schematic, partially sectional view according to a second embodiment of the invention. In this embodiment, the calotte has an axial recess 60 on, as a stepped bore 60 is designed. This has a part 61 the axial recess 60 an inner diameter 62 that is larger than an inside diameter 63 a part 64 the axial recess 60 is. In this way, a sufficient wall thickness in the region of the calotte head 24 be achieved.

The axial recess 60 extends completely through the calotte body in this embodiment 25 and in the calotte head 24 into it. Due to the selected configuration of the axial recess 60 can the mass of the dome 23 be set. Thus, with respect to the given spring-mass system, a vote of the opening and closing behavior of the high-pressure directional valve 2 respectively. Here are numerous modifications conceivable.

In a possible modification, the axial recess 60 from the dome foot 26 out only in the calotte body 25 extend. About the inside diameter 62 and the depth of the axial recess 60 Here is within certain limits the mass of the dome 23 adjustable. In a further possible embodiment, for example, the part 64 the axial recess 60 omitted. The axial recess 60 can then as a blind hole 61 be designed.

The respective configuration of the axial recess 60 has no or only a negligible influence on the flow through the high-pressure directional valve 2 , Specifically, there are no special requirements for the design of the axial recess 60 to deliver. In contrast to a dome, which has bore intersections in the area of the dome head, this results in a significant reduction of the manufacturing effort.

The invention is not limited to the described embodiments.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009003054 A1 [0002, 0003]

Claims (10)

High pressure directional valve ( 2 ) for a component of a fuel injection system, which is used in particular for air-compressing, self-igniting internal combustion engines, with one of a valve wall ( 21 ) limited valve space ( 22 ), one in the valve space ( 22 ) arranged valve closing body ( 40 ), with one on the valve wall ( 21 ) formed valve seat surface ( 41 ) cooperates to a sealing seat, and a spring element ( 30 ), which the valve closing body ( 40 ) along a valve axis ( 27 ) against the valve seat surface ( 41 ) acted upon, characterized in that the valve closing body ( 40 ) on a calotte head ( 24 ) a dome ( 23 ) is formed, that the calotte ( 23 ) one with the calotte head ( 24 ) connected calotte body ( 25 ), that the calotte ( 23 ) on its calotte body ( 25 ) on the valve wall ( 21 ) along the valve axis ( 27 ) and that the calotte body ( 25 ) at least one lateral recess ( 43 . 44 ), which is designed such that between the calotte body ( 25 ) and the valve wall ( 21 ) a fuel passage ( 45 . 46 ) which forms a fuel flow from the sealing seat ( 42 ) to one of the calotte head ( 24 ) facing away from Kalottenfuß ( 26 ) of the calotte ( 23 ). High-pressure directional valve according to claim 1, characterized in that at least one lateral recess ( 43 . 44 ) as a lateral flattening ( 43 . 44 ) is configured and / or that at least one lateral recess ( 43 . 44 ) as at least substantially flat and / or at least substantially rectangular lateral flattening ( 43 . 44 ) is configured. High-pressure directional valve according to claim 1 or 2, characterized in that on the Kalottenfuß ( 26 ) a support surface ( 34 ) and a retaining ring ( 35 ) are formed, that the retaining ring ( 35 ) the support surface ( 34 ) encloses sections that the spring element ( 30 ) on the support surface ( 34 ) of the calf's foot ( 26 ) and that the retaining ring ( 35 ) at least one interruption ( 48 . 49 ), which from the fuel passage ( 45 . 46 ) between the lateral recess ( 43 . 44 ) of the calotte body ( 25 ) and the valve wall ( 21 ) to an axial fuel channel ( 32 ) leads. High-pressure directional valve according to claim 3, characterized in that a spring holder ( 28 ) is provided, on which the spring element ( 30 ) is supported, and that the axial fuel channel ( 32 ) axially through the spring holder ( 28 ) leads. High-pressure directional valve according to claim 3 or 4, characterized in that the interruption ( 48 . 49 ) of the retaining ring ( 35 ) geometrically the lateral recess ( 43 . 44 ) of the calotte body ( 25 ) assigned. High-pressure directional valve according to one of claims 3 to 5, characterized in that the interruption ( 48 . 49 ) of the retaining ring ( 35 ) as a groove-shaped interruption ( 48 . 49 ) is configured. High-pressure directional valve according to one of claims 1 to 6, characterized in that the calotte head ( 24 ) an outer cross-section ( 55 ) in a projection along the valve axis ( 27 ) within an outer cross section ( 56 ) of the calotte body ( 25 ) lies. High-pressure directional valve according to one of claims 1 to 7, characterized in that the calotte ( 23 ) an axial recess ( 60 ) extending from the calotte foot ( 26 ) at least in sections through the calotte body ( 25 ), and / or that the dome ( 23 ) an axial recess ( 60 ) extending from the calotte foot ( 26 ) from at least the calotte body ( 25 ) and optionally in sections through the calotte head ( 24 ). High-pressure directional valve according to one of claims 1 to 8, characterized in that the calotte body ( 25 ) at least two correspondingly configured lateral recesses ( 43 . 44 ) which face each other with respect to the valve axis ( 27 ) are opposite. High pressure pump ( 1 ), in particular for fuel injection systems of air-compressing, self-igniting internal combustion engines, with at least one pump assembly ( 7 ), which has a pump work space ( 10 ), and a high-pressure directional valve ( 2 ), wherein the pump work space ( 10 ) via the high-pressure directional valve ( 2 ) with a fuel connection ( 4 ) and wherein the high-pressure directional valve ( 2 ) is designed according to one of claims 1 to 9.

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