DE10046416A1 - Valve configuration for control valves comprises a valve seat between a high pressure inlet and a blocking element on the low pressure side which in its closed position is centered over the seat contact zone - Google Patents

Abstract

Valve configuration for control valves comprises a valve seat between a high pressure inlet and a blocking element (7) on the low pressure side which in its closed position is centered over the seat contact zone. A receiving chamber (16) limited on the lower pressure side is assigned to the blocking element on the seat contact zone. Preferred Features: The blocking element forms a component connected to an adjusting movement device (9).

Description

The invention relates to a valve design for control valves according to the preamble of claim 1.

Valve designs of the aforementioned type are from practice known. Corresponding to that for fuel injection systems machines, especially storage pressure injection systems prevailing, very high pressures up to the order of The control valves also have a growing pro of 2000 bar bleme, because the lying between high and low pressure side Valves with their shut-off flow from the high pressure side are subject to very high loads. Insbeson This leads to the pressure drop between the high and low pressure side in the throttle point with high flow velocities the tendency of the flow to cavitate with increasing pressure waste in the exit area on the locking member, with the Impact on the blocking member because of the order involved steering and flow delays again an increase in pressure results. This favors the imploding of the cavitation bubbles in the seat contact area of the locking member and the seat of the Valve seat and causes corresponding cavitation erosion. This affects the locking element and the valve seat those areas that, due to their function, also have the highest mechanical  Exposed to loads, such as through impact act upon the impact of the locking member on the Valve seat and by aligning the locking member opposite the seat of the Zen associated with the closing process tration of the locking member opposite the seat.

The invention has for its object a valve design of the type mentioned at the beginning with regard to the pro to improve bleme and especially the danger of Kavitati to reduce erosion in such valve designs.

According to the invention this is through the features of the claim 1 achieved using the thought by graduated pressure reduction the requirements for cavitation largely eliminate. For this purpose it is provided that, related on the closed position of the locking member, adjacent to the locking member to the seat contact zone against the low pressure side limited and throttled connection to the low pressure side standing recording room is assigned. Limiting this Room opposite the seat contact zone can be more appropriate as a guide for the locking member, and / or serve as a throttle point, so that the desired graduated throttling also structurally with simple means and with can be realized with little effort.

The locking member can be an independent within the scope of the invention Be a component, or with the assigned position gungstransfer connected, being as an actuating movement lazy stamp with relative to their length small diameter can serve, so that the mutual  Do not align the seat with the pressure stamp is impaired.

Serves the space delimitation of the second, outlet-side throttle area at the same time as Füh tion for the locking member, so it can also stabilize the flow conditions in the transition from the first throttle Range to be reached on the locking member, which is also on reducing or avoiding cavitation of the currents tion or the cavitation erosion proves to be expedient.

Solid balls, Ku gel segments or ver in the direction of the seat recent valve bodies are used, in particular for spherical, and especially for solid spherical pawls tion is appropriate.

In terms of realizing different, throttled ter connections of the respective locking member at least partially wise surrounding space to the low pressure side valve seats in a spherical or spherical shape dung or tapered training, especially in flat tapered training prove to be appropriate, so that ver different throttle paths, possibly also combined, real let sieren, regardless of the type of Formation of the part forming the guide, this being the case can also be designed as an aperture.

Constructively, it can be useful for this purpose, seat and on the seat following the guide part separate components  assign, for example the leadership part, in the sense of aperture mentioned above or in the sense of a zy Lindrischen leadership, to assign a cover plate attached to a connects the valve seat containing valve plate, with zwi rule cover plate and valve plate if necessary as a throttle provide serving channel connections can be arranged.

The invention also makes it possible with simple means Throttle cross section of the space delimited by the guide to make dependent on the stroke of the locking member, ie one stroke dependent throttle connection with variable cross-section fen, the corresponding cross-sectional changes also through appropriate shaping for the actuator in the form of an actuating plunger or pressure stamp and / or the locking member can be realized.

Further details and features of the invention emerge from the claims. Furthermore, the invention is set forth below hand of an embodiment explained in more detail. Show it:

Fig. 1 is a schematic sectional view of the control valve of an injection injector, between the nozzle part and an opposing to this arranged magnetic actuator, the control valve, the magnetic actuator on the control valve acts on a stroke actuator for the locking member, which controls a throttled inlet from a pressure chamber with which the nozzle needle of the injection nozzle, which is acted upon by the injection medium in the opening direction on the high-pressure side, is connected to an application surface via which the nozzle needle is loaded in addition to the closing spring in the closing direction when the pressure in the pressure chamber is present,

Fig. 2 shows an enlarged detail of a portion A of FIG. 1, showing the locking member constricting beaufschla actuating movement transmitter and the related contractual area of the valve seat,

Fig. 3 is a FIG. 2 corresponding inventive design of locking element and an associated valve seat portion,

Fig. 4 shows a section according to IV-IV in Fig. 3 in schemati lized representation,

Fig. 5 and 6 show further embodiments of the invention in one of the Fig. 4 corresponding representation, analogous to Fig. 4, the locking member between zugehö engined seat and axially spaced guide has a throttle area with the front seat area of the actuator branching orifices or throttle channels,

Fig. 7 shows a further embodiment according to the invention, in which the throttle cross sections in the radial guide portion of the axially movable locking of Glienicke are laid,

Fig. 8 is a sectional view according to line VII-VII,

Fig. 9 shows another embodiment of the invention, in which the throttle cross sections are variable depending on the stroke of the locking member, and

Fig. 10 is a schematic sectional view according to Li never XX in Fig. 9.

In Fig. 1, the control valve 1 of a not shown Darge injector is illustrated, via which the injector associated with the injector is controlled. The high pressure side inlet connection to the control valve 1 is illustrated by the arrow 2 . The inlet takes place via a bore 4 provided in a valve plate 3 , which opens out onto a valve seat 6 via a throttle point 5 .

The valve seat 6 tapers in the direction of the bore 4 , that is, counter to the inflow direction according to arrow 2, and the valve seat 6 is assigned a locking member 7 which is supported in a stroke-movable manner (arrow 8 ). The support of the locking member 7 he follows in the embodiment ( Fig. 1) via a Stellbewe supply transmitter 9 , which is designed as a rod-shaped, thin actuating plunger and which is based on the Steuer erventil 1 to the direction of flow according to arrow 2 opposite via a magnetic actuator, not shown here the injector is loaded and adjustable.

In the closed position, the locking member 7 is seated in a seat contact zone 10 on the valve seat 6 , to which a bore 11 in the valve plate 3 connects to the low-pressure side, into which the locking member 7 supported by the actuating motion transmitter 9 is immersed and which, based on FIG. 1 and 2, forms part of the low-pressure outflow path which, as can be seen in FIG. 1, continues in transverse channels 12 which lie between valve plate 3 and housing 13 of control valve 1 , where in the exemplary embodiment the valve plate 3 against the housing 13 via a Clamping ring 14 is centered and fixed.

In connection with the high pressure on the high pressure, there are very high flow velocities, based on the opening position of the blocking member 7 , which is not shown, when flowing through the throttle point 5 , which cause cavitation of the flow due to the transfer of the flow medium to the low pressure side due to the pressure drop can, where the cavitation bubbles when they hit the locking member 7 and the locally associated deflection and flow delay can implode, which can lead to locking member 7 and valve seat 6 for cavitation erosion.

This is where the invention comes in, as explained with reference to FIGS . 3 to 9 below, the same reference numerals being used for the same parts.

Fig. 3 illustrates that the designed as a spherical segment in the embodiments, locking member 7 a on the Boh tion 11 tuned diameter which such a way that in the direction parallel to the seat contact zone 10 the center plane 15 of the locking member 7, a radial guide is given by the bore 11, which allows the stroke mobility - according to arrow 8 - of the locking member 7 in the sense of a low-friction sliding guide, but delimits a space 16 downstream from the seat surface 10 due to the guide serving as a gap seal, from which the connection to the low-pressure side follows throttled. This throttled connection is illustrated in FIG. 3 via bores 17 which open onto the space 14 adjacent to the valve seat 6 and which run radially to the stroke axis 18 of the actuating movement transmitter 9 .

In the transition from the high-pressure side (arrow 2 ) to the low-pressure side - symbolized in FIG. 3 by the arrows 19 - two throttling points follow one another, so that a staged pressure reduction with a correspondingly lower pressure drop at the throttling point 5 in the inflow onto the blocking member 7 results, whereby the conditions with regard to the occurrence of Ka vitationserosion are significantly mitigated.

The intended axial guide for the locking member 7, through which the throttle chamber 16 between the seat 10 and the throttle point is defined 5 and downstream restriction holes 17 carries furthermore also contributes, that the locking member 7 ent one of its locking position and in its raised from the valve seat 6 Location speaking Centering maintains what contributes to the stabilization of the flow conditions on the locking member 7 and the flow conditions with respect to the locking member 7 and also reduces the mechanical stresses between locking member 7 and valve seat 6 in that deviations in the axial position are at least largely avoided.

The centering guide function for the locking member 7 proves to be expedient if the locking member 7 is firmly connected to the actuating transmission 9 or, without a centering connection to it, is only acted upon. Furthermore, the guide function proves to be expedient in connection with full-spherical locking members, or also locking members designed as a spherical segment, wherein in the exemplary embodiment a spherical segment is provided as a locking member 7 . Instead kugeli ger locking members 7 may also be provided in the direction of the valve seat tapered, in particular conical or tapered locking members. 7

Fig. 5 and 6 illustrate solutions which functionally the accordingly, what has been with reference to FIGS. 3 and 4 explained. 3 and 4 in the structural design, they differ from the solution according to FIGS . 3 and 4 by the type of implementation of the connection of the throttle chamber 16 to the low pressure side via corresponding throttle bores or throttle channels, throttle channels 20 being provided in the embodiment according to FIG. 5, which, starting from the throttle chamber 16 to the low pressure side (arrow 19) open out, the throttle channels are formed by in Fig. 5, that a valve plate 21 is provided, which is plate-allocated 22 a cover, said valve plate 21 and cover plate 22 between their mutually facing surfaces channels 20 bil, which are incorporated in the cover plate 22 , in the valve plate 21 or in both plates and which run in the Teilungsebe ne 23 of the two plates. The parting plane 23 speaks the section plane between the bore 11 and the conical valve seat 6 , so that the bore 11 extends in the cover plate 22 and the valve seat 6 is machined into the valve plate 21 . Overall, this leads to a simplified structure.

FIG. 6 again assumes a division into valve plate 24 and cover plate 25 , as was explained with reference to FIG. 5. The valve seat 26 is also incorporated into the valve plate 24 , the bore 11 is assigned to the cover plate 25 and passes through it, opening out within the diameter of the valve seat 26 on this. Accordingly, the expanding in the direction of flow according to arrow 2 valve seat 26 has a radial overlap area to the cover plate 25 , the part level between valve plate 24 and cover plate 25 with 27 be marked and is offset against the flow direction 2 to the central plane 15 of the locking member 7 , which is axial lies in the area of the bore 11 , so that in this solution, too, the guide for the locking member 7 is in the area of the bore 11 , in FIG. 5 in the area of the cover plate 22 , in FIG. 6 in the cover plate 25 . Characterized in that the diameter of the bore 11 is smaller than the diameter of the conical valve seat 26 in the region of the part plane 27 , the throttle chamber 28 is partially covered by the side of the cover plate 25 facing the valve plate 24 , so that on the. Throttle chamber 28 which can open throttle bores 30 axially penetrating the cover plate 25 . The invention thus shows a wide variety of connection options of the respective throttle chamber 16 or 28 to the low pressure side, so that corresponding design requirements can be taken into account within the scope of the invention.

Another possibility of the throttling connection to the low pressure side is shown in FIGS . 7 and 8, with an initial situation also being given here as it corresponds in principle to the construction according to FIGS. 3 to 6. The valve plate 31 , as an inlet on the high-pressure side according to arrow 2, in turn has a bore 4 , which opens out centrally via a throttle point 5 onto the valve seat 6 , which in the closed position of the blocking member 32 is covered by the latter. In this exemplary embodiment, a ball segment is also provided as the locking member 32 , the central plane 15 of which runs parallel to the seat contact surface 10 and which is guided axially displaceably in the region of the central plane 15 and bears sealingly against the wall of the bore 33 , which acts as a guide bore for the locking member 32 on the seat surface 6 closes and delimits the throttle space 34 to the seat 6 together with the locking member 32 . In this case too, the locking member 32 is supported by an actuating movement transmitter 9 which can be moved in accordance with the arrow 8 . As illustrated in FIG. 8, the throttle chamber 34 is connected to the low pressure side via axially extending recesses provided in the circumference of the bore 33 , which are designated by 35 and which extend in the direction of stroke movement (arrow 8 ) on both sides of the central plane 15 , such that that, analog to the Drosselboh stanchions 17 or the throttle channels 20 or the throttle bores 28 , regardless of the respective stroke position of the locking member 32, there is a throttling connection of the space 34 to the low pressure side te. For this purpose, it may be expedient to design the actuating movement transmitter 9 , which is designed as a punch or as an actuating rod, with a diameter smaller than the blocking member 32 , so that the incorporation of further channels or bores is eliminated.

Starting from a basic design according to FIGS. 7 and 8, FIGS. 9 and 10 show an embodiment in which in turn one works with a locking member 36 designed as a spherical segment, which in the region of its central plane 15 parallel to the seat contact zone 10 against the wall of the bore 38 abuts, which serves as a guide for the locking member 36 and with respect to and the subsequent valve seat 6, the locking member 36 delimits the throttle space 37 . This are in the direction of the low-pressure side opening discharge cross-sections assigned, which are cross-sections as throttles in the size of their cross-sectional area of the stroke position of the locking member 36 dependent. These stroke-variable throttle cross sections are formed by recesses 40 in the circumference of the throttle bore 39 , which can be designed according to the desired throttle behavior. Thus, in FIGS. 9 and 10 illustrate, as an example a configuration of light, in the closed position of the locking member 36, the out recesses in the largely controls abge 40 via the locking member 36 at least and be released only with increasing opening stroke.

Various possibilities are therefore within the scope of the invention given a stepped throttle transition from high to never derdruckseite for control valves of the type described to rea lize, both with regard to cavitation erosions such as also with regard to the mechanical wear of the locking member and valve seat solutions are created that last and last Improve the reliability of the control valve.

Claims (31)

1.Valve training for control valves, in particular for control valves of injection injectors operated with diesel or heavy oil and working with accumulator pressure injection, preferably large-volume internal combustion engines, with a valve seat, which is located between a high-pressure inlet and a low-pressure blocking element, in its The closed position of the valve seat, which tapers in the closing direction, is centered over its seat contact zone, is acted upon in the direction of its closed position against the direction of flow by a stroke-movable actuating movement transmitter, and is opposite a throttle section on the high-pressure side in the inlet to the valve seat, characterized in that the blocking element ( 7 ; 32 ; 36 ), in relation to the closed position, adjacent to the seat contact zone ( 10 ) is delimited against the low pressure side and is connected to the low pressure side in a throttled connection space ( 16 ; 28 ; 39 ). 2. Valve design according to claim 1, characterized in that the locking member ( 7 ; 32 ; 36 ), based on the closed position, in the area adjacent to the seat contact zone ( 10 ) in a restricted area against the low pressure side ( 16 ; 28 ; 39 ) lies. 3. Valve design according to claim 1 or 2, characterized in that the seat contact zone ( 10 ) opposite boundary of the space ( 16 ; 28 ; 39 ) by a valve seat ( 6 ) zen trical guide for the locking member ( 7 ; 32 ; 36 ) is formed. 4. Valve design according to one of the preceding claims, characterized in that the locking member ( 7 ; 32 ; 36 ) forms an independent component from the actuating transfer device ( 9 ). 5. Valve design according to one of claims 1 to 3, characterized in that the locking member ( 7 ; 32 ; 36 ) forms a component connected to the actuating movement transmitter ( 9 ). 6. Valve design according to one of the preceding claims, characterized in that a valve ball is provided as the blocking member ( 7 ; 32 ; 36 ). 7. Valve design according to one of claims 1 to 5, characterized in that a ball segment with the actuating movement transmitter ( 9 ) associated flat side is provided as the blocking member ( 7 ; 32 ; 36 ). 8. Valve design according to one of claims 1 to 5, characterized in that a valve body which tapers conically in the closing direction is provided as the blocking member ( 7 ; 32 ; 36 ). 9. Valve formation according to claim 8, characterized, that the valve body is opposite to its conical Taper runs out cylindrically. 10. Valve design according to one of the preceding claims, characterized in that the valve seat ( 6 ; 26 ) in the region of the seat surface is spherical, in particular dome-shaped. 11. Valve body according to one of claims 1 to 9, characterized in that the valve seat ( 6 ; 26 ) is conical in the region of the seat surface, in particular as a flat truncated cone. 12. Valve body according to claim 10 or 11, characterized in that a cylindrical guide part (bore 11 ; 33 ; 38 ) is provided as a guide on the valve seat on the low pressure side. 13. Valve design according to claim 12, characterized in that the cylindrical guide part (bore 11 ; 38 ) adjoins the surface of the valve seat ( 6 ). 14. Valve design according to claim 12, characterized in that the valve seat ( 26 ) overlaps the cylindrical guide part (bore 11 ) radially outwards. 15. Valve design according to one of claims 12 to 14, characterized in that the guide part (bore 11 ) is integrally formed with the valve seat ( 6 ). 16. Valve seat according to one of claims 12 to 14, characterized in that a valve plate ( 21 ) containing the valve seat ( 6 ) is assigned a cover plate ( 22 ) which contains the guide part (bore 11 ). 17. Valve design according to one of the preceding claims, characterized in that the space delimited by the guide to the seat contact zone ( 10 ) ( 16 ) has a radial connection (bore 17 ; channel 20 ) to the low-pressure side. 18. Valve design according to claim 16 and 17, characterized in that the radial connection by at least one radial, through valve plate ( 21 ) and cover plate ( 22 ) limited throttle channel ( 20 ) is formed. 19. Valve arrangement according to claim 17, characterized in that the radial connection is formed by at least one radial throttle bore ( 17 ). 20. Valve arrangement according to one of claims 1 to 16, characterized in that the space delimited by the guide ( 16 ) has an axial connection (bore 28 ; recess 35 ; 40 ) to the low pressure side. 21. Valve arrangement according to claim 20, characterized in that the axial connection is formed by an axial bore ( 28 ) offset radially for guidance (bore 11 ). 22. Valve design according to claim 21, characterized in that the axial bore ( 28 ) is provided in the cover plate ( 25 ). 23. Valve design according to claim 21, characterized in that the axial connection comprises a recess ( 35 ) provided in the circumference of the guide (bore 33 ). 24. Valve design according to claim 23, characterized in that the axial connection is provided by recesses ( 35 ) provided in a regular arrangement in the circumference of the guide (bore 33 ). 25. Valve formation according to claim 20, characterized, that the axial connection by the scope of the guide arranged area of the locking member provided recesses and / or flattening is formed. 26. Valve design according to one of the preceding claims, characterized in that the space delimited by the guide ( 39 ) has a cross-section-dependent throttle connection (recess 40 ) to the low-pressure side of the stroke of the locking member ( 36 ). 27. Valve design according to claim 26, characterized in that the cross-section-dependent throttle connection is formed by recesses ( 40 ) provided in the circumference of the guide. 28. Valve design according to claim 26 or 27, characterized in that the recess ( 40 ) has a cross section widening in the stroke direction to the low pressure side. 29. Valve formation according to claim 26, characterized, that the cross-section dependent throttle connection by im Scope of the locking member provided recesses and / or Ab is formed. 30. Valve formation according to claim 29,  characterized, that the recess cross-sectionally in the stroke direction High pressure side extended. 31. Valve formation according to one of claims 23 to 30, characterized, that the cross section in the stroke direction is variable of one lying in the area of the guide cross-section Cross-sectional level.