EP1407132B1 - Solenoid valve comprising a plug-in/rotative connection - Google Patents

Abstract

The invention relates to a solenoid valve for a fuel injector for injecting fuel into the combustion chamber of an internal combustion engine, said valve comprising an injector (1), which contains an electromagnet (19). The latter is used to actuate an armature assembly of the solenoid valve (18) for relieving the pressure in a control chamber (3), thus causing a nozzle needle or tappet assembly (2) in the injector (1) to carry out an opening or closing movement. The armature assembly contains a first and a second armature part. The first armature part (30) and the second armature part (36) are joined together by a plug-in/rotative connection (31, 38; 47), whereby one of the armature parts (30, 36) is encompassed by an armature guide (41), which contains rotational locking elements (42, 43, 52).

Description

Technical area

Solenoid valves can be used on fuel injection systems for actuating fuel injectors be used. For this purpose, the solenoid valves comprise a recessed into the injector body Electromagnet, which cooperates with an anchor group, the one Anchor bolt and an anchor plate comprises. The anchor bolt is designed so that This is a closing body is added, the a drain of the nozzle needle of the Fuel injector actuated control chamber closes or releases. To achieve a fast responding and accurate lifting movement of the anchor group upon excitation of the Electromagnet is a reliable and backlash-free connection of anchor plate and Anchor bolts for two-piece anchor assemblies or for anchor guide sleeve and anchor bolts required for one-piece anchors.

State of the art

DE 199 36 943 A1 relates to a fuel injection valve which is one of an actuating device Having a valve needle body operable by means of a valve needle body, which cooperates with a valve seat surface to a sealing seat. Pressing the valve closing body To the valve seat surface via a return spring, which has an anchor plate and a valve needle body acts on the valve closing body. The anchor disc is secured by a locking element to the valve needle body. In the illustrated Embodiment, the locking element is made in two parts and can be made a mother and a lock nut exist.

DE 196 50 865 A 1 and WO 98/25025 relate to a solenoid valve. Its anchor is designed in several parts. The anchor comprises an anchor plate and an anchor bolt, which is guided in a slider. To reverberate the anchor plate after a Closing the solenoid valve to avoid is on the armature a damping device educated. With such a device are exactly the required short Switching times of the solenoid valve sustainable and reproducible. This solenoid valve is determined for use in injection systems, in particular high-pressure injection systems such for example, those with high-pressure accumulator (common rail).

The damping device, with the ringing of the first anchor part in its dynamic Displacement is dampable, comprises a first anchor part, the one in axial Has a directional approach that is complementary to the approach, fixedly arranged recess of the slider at a displacement of the first anchor member can dive. The recess with the approach closes a damping chamber one which has a leakage gap connection with a discharge space surrounding it Has.

Alternatively, an annular shoulder can be arranged on the anchor bolt, the part of a the first anchor part is enclosed and at the first anchor part also an annular shoulder is attached, between the and the annular shoulder of the anchor bolt constantly Damping space is included, in turn, a connection via a leakage gap to a surrounding relief space has.

According to this solution with an actuatable by the electromagnet two-part Anchor is inserted between the anchor bolt and the anchor plate a stop ring. The stop ring is designed as an open lock washer and tends to knock out. It can be more severe signs of wear, on the one hand to adjusting Game between anchor bolt and anchor plate and on the other to complete destruction can cause the backup washer. Already a self adjusting game between Anchor bolt and anchor plate influences the quantity tolerances during injection disadvantageous, so that in particular a reproducibility at successive intervals at short intervals Injections of very small quantities is no longer possible.

Presentation of the invention

The solution of the invention is characterized by its simplicity and its Robustness. The assembly can be done easily without special tools; especially is an accurate adjustment of the components of the anchor group to each other possible. By arranging an armature guide to the bolt-shaped anchor part in two-piece Execution of the anchor is given an extension of the anchor guide, so that a higher Guidance accuracy of the bolt-shaped anchor member can be achieved. A higher one Fühivngsgenauigkeit offers advantages in short successive switching operations of Solenoid valve on the fuel injector.

With the solution according to the invention can, depending on the variant in two-part Anchoring a slight pre-assembly done. In multi-part anchors can - about means a bayonet closure - a simple and safe to handle joining the first anchor assembly, after pre-assembly in an armature guide provided with guide sections can be admitted, done. The components to be joined together can with the inventive solution in terms of security against rotation by component solid or additional measures are secured relative to each other in their rotational position. It is possible, on the one hand, into an opening in which the anchor components to be joined are twisted to each other to engage the portion of an elastic anchor spring. An extension of the elastic armature spring can be configured in, for example, a longitudinal groove Recess protrude at the anchor guide. This is when operating one of two Components of the assembled armature assembly on the fuel injector ensure that the one another twisted and secured components remain in the twisted position and a trouble-free operation over a long time is guaranteed.

In a further embodiment variant of the solution proposed according to the invention a slotted anchor plate and an anchor bolt with each other in such a way be joined, that rejuvenated in forming the anchor bolt with an area Diameter tapered provided with a slot anchor plate over the area Diameter introduced and then pushed up on the anchor bolt becomes. Subsequently, the assembly of the example performed grooved armature guide on the area of tapered diameter and twisting of the anchor bolt, until the stop surface and formed on the armature guide groove twisting the Anchor guide to the pre-assembled module, consisting of anchor plate and anchor bolt, prevent.

By means of the bayonet solution no additional rotation of the anchor plate is needed. All illustrated embodiments of the solution according to the invention are common, that they are for above and below a valve clamping nut clamped anchor guides can be used.

drawing

With reference to the drawing, the invention will be described below in more detail.

Figur 1

eine zweiteilig ausgebildete Ankergruppe, bei der Ankerplatte und Ankerbolzen mit einer Sicherungsscheibe verbunden sind,

Figuren 2.1 und 2.2

einen Ankerbolzen mit Verdrehsicherung in Draufsicht und Seitenansicht,

Figuren 3.1 und 3.2

die Ausführung einer Ankerplatte in Schnitt- und Draufsicht,

Figuren 4.1 bis 4.3

einen in Nuten geführten Ankerbolzen, der in einer Ankerführung aufgenommen ist,

Figur 5

einen einteilig konfigurierten nicht erfindungsgemäßen Anker, der von einer genuteten Ankerführung umschlossen ist und an seinem unteren Ende eine Bajonettsicherung aufweist,

Figur 6.1

eine geschlitzt konfigurierte Ankerplatte,

Figur 6.2

die Detaildarstellung einer montierten Ankergruppe

Figur 6.3

die Draufsicht auf eine geschlitzte Ankerplatte,

Figur 6.4

den Schnittverlauf A-A gemäß Figur 6.2 und

Figur 6.5

einen im Vergleich zur Darstellung gemäß Figur 6.2 um 90° gedrehten Ankerbolzen.

It shows:

FIG. 1

a two-part anchor group, are connected to the anchor plate and anchor bolt with a lock washer,

Figures 2.1 and 2.2

an anchor bolt with anti-rotation in plan view and side view,

Figures 3.1 and 3.2

the execution of an anchor plate in section and plan view,

Figures 4.1 to 4.3

a guided in grooves anchor bolt, which is accommodated in an armature guide,

FIG. 5

a one-piece configured anchor not according to the invention, which is enclosed by a grooved anchor guide and has a bayonet securing at its lower end,

Figure 6.1

a slotted configured anchor plate,

Figure 6.2

the detailed representation of a mounted anchor group

Figure 6.3

the top view of a slotted anchor plate,

Figure 6.4

the section AA according to Figure 6.2 and

Figure 6.5

an anchor bolt rotated by 90 ° compared to the illustration according to FIG. 6.2.

variants

FIG. 1 shows a two-part armature assembly, in the armature plate and anchor bolt are provided with a lock washer.

The representation according to FIG. 1 shows that in an injector body 1 a Fuel injector a nozzle needle / plunger assembly 2 provided in an injector body 1 Control room 3 is included. The control chamber 3 is via an inlet throttle 4 acted upon by a control volume and is via a pressure-relieving the control chamber 3, 8 operable outlet throttle 7 aufsteuerbar by a closing body. A front page the nozzle needle / plunger assembly 2 protrudes into the control chamber 3, which of a Enclosed boundary wall 6. Depending on pressure or pressure relief of the control chamber 3 is the projecting with its end face 5 in this nozzle needle / plunger assembly 2 imprinted a vertical movement within the injector body 1, in the injection openings, not shown here, of the fuel injector on the combustion chamber the internal combustion engine either closed or opened.

The actuatable by means of a solenoid valve 18 closing body 8 is in Figure 1 in his Valve seat 9 shown reproduced, wherein the closing body 8 of a with the armature assembly 12, 13 enclosed molding 10 is enclosed.

The representation of Figure 1 is also removed that the anchor bolt 12 the anchor group 12, 13 is enclosed by a bolt guide 11, by means of a screw-in received in the injector body 1 of the fuel injector. The two Components 12 and 13 of the multi-part configured armature are via a coil spring trained biasing member 14 biased against each other, wherein between the Slider 13 and the anchor bolt 12, a distance 15 is set. In the upper area of the slider 13 is a recess provided in which a locking ring 16 is admitted. The retaining ring 16 according to this embodiment is via a Valve spring 17 is applied, the one electromagnet 19 of the solenoid valve 18 in a Drilled through hole. This solution tends to knock out the locking ring 16, the an end is open. The disadvantage of this construction is, above all, to be seen in that more severe signs of wear can occur, even in an extreme case can lead to the destruction of the lock washer 16.

For the sake of completeness it should be mentioned that on the electromagnet 19 of the solenoid valve 18th a magnet sleeve 20 is formed. The magnet sleeve 20 is supported on a in a bore the injector body 2 inserted shim 21 from. On the outside of the injector body 2, an external thread 22 is provided, with which one with a thereto correspond internally threaded magnetic clamping nut the electromagnet 19 and so that the solenoid valve 18 is fixed to the injector body 1.

Figures 2.1 and 2.2 show an anchor bolt with anti-rotation in plan view and in side view.

From the plan view according to the illustration in Figure 2.1 shows that the anchor bolt an annularly configured abutment surface 35, which in a comparison to Anchor bolt diameter 33 enlarged diameter is formed. The lateral surface of the anchor bolt is indicated by reference numeral 34. At the anchor bolt is about it In addition, a projection 31 was added, the surfaces 32 has. The approach 31 is dimensioned that this is on both sides over the lateral surface 34 of the bolt-shaped anchor part extends.

From the side view of the anchor bolt 30 of Figure 2.2 shows that the anchor bolt 30 is made in a bolt diameter 33. The approach 31 with the trained Surfaces 32 has an approximately rectangular shape; at the neck 31 on the anchor bolt 30 joins a range of tapered diameter, for example, with an external thread can be provided.

Figures 3.1 and 3.2 is a sectional view and shown in plan view to take an anchor plate. From the sectional view according to Figure 2.1 shows the anchor plate 36 comprises a central bore 37. The central bore 37 is of an approximately rectangular configured opening 38 enclosed, the dimensions of which the dimensions of the approach surface 31 with surfaces 32 formed on the anchor bolt 30 corresponds.

From the plan view of the anchor plate according to Figure 3.2 shows that the anchor plate 36 provided at its periphery with approximately triangular-shaped recesses 39 is. The bore 37 in the anchor plate 36 is in a rectangularly configured opening 38th over, by which during joining by insertion and rotation of the anchor bolt 30th a pre-assembled anchor assembly is created. Seen in the radial direction, the run triangular configured recesses 39 on the circumference of the anchor plate 36 in individual Slots 40 off.

From the illustrations according to Figures 4.1 to 4.3 is a pre-assembled, two-piece configured Anchor assembly protruding at the bottom of one with guide sections provided anchor guide 41 is enclosed.

Thus, the illustration according to FIG. 4.1 shows a preassembled armature assembly from the anchor bolt 30 and the anchor plate 36. In the illustration according to FIG. 4.1 the projection 31 on the anchor bolt 30 is rotated so that its surfaces 32 perpendicular to the plane run. The approach 31 runs - as already mentioned - in a threaded section from, which enclosed in the illustration of Figure 4.1 by a valve spring 17 is. Below the anchor plate 36, the anchor bolt 30 is enclosed by an armature guide 41. The armature guide 41 is located on the annular stop surface 35th of the anchor bolt 30. The armature guide 41 is seen in the longitudinal direction with a groove-shaped extending portions 42 and 43, namely, a first guide groove 42 and a second guide groove 43. As the illustration taken in Figure 4.1 can be, serves the second longitudinally extending longitudinal groove 43 for receiving an acting as anti-rotation 44 anchor spring. The anchor spring intersperses the in Figure 4.1, not shown, opening 38 which is formed substantially rectangular (See illustration according to Figure 4.3).

Figure 4.2 shows a longitudinal section through the preassembled armature assembly, wherein the Anchor guide 41 is not shown for illustrative reasons.

The valve spring 17, which acts on the anchor plate 36, is supported on the upper End face of the projection 31 from. In the view of Figure 4.2, the surfaces 32 of the approach 31 to recognize. The trained as an anchor spring, for example, anti-rotation 44th extends parallel to the bore 37 of the anchor plate whose rectangular shape to the rectangular shape the approach 31 of the anchor bolt 30 with surfaces 32 corresponds.

The plan view as shown in Figure 4.3 is one of anchor bolt 30 and anchor plate 36 assembled and secured against rotation pre-assembled anchor assembly. to Assembly of anchor bolts 30 and anchor plate 36 are formed on the anchor bolt 30 Approach 31 and the bore 37 of the anchor plate 36 surrounding opening 38 in alignment aligned with each other, so that the anchor bolt 30 pushed through the anchor plate 36 can be. Thereafter, the anchor plate 36 is formed with opening 38th twisted relative to the shoulder 31 of the anchor bolt 30 and in the opening 38 a rotation inserted in the form of an anchor spring which in one of the longitudinal grooves 42 and 43rd the armature guide 41 protrudes, but in the illustration 4.3, however, by the anchor plate 36th are covered. By means of the configured as an anchor spring anti-rotation 44 is a Twist of anchor bolt lug 31 and the opening 38 of the anchor plate 36 to each other prevented, so that the pre-assembled anchor assembly always remains attached as such.

FIG. 5 shows an integrally configured armature, which is characterized by a grooved armature guide in FIG enclosed in an injector housing.

In the injector body 1 of a fuel injector is analogous to the illustration of Figure 1 a Nozzle needle 2 is received, which protrudes into a control chamber 3 of the injector body 1. The nozzle needle / plunger assembly 2 is analogous to the known from the prior art Variant on the pressure prevailing in the control chamber 3 in the vertical direction in the injector body 1 actuated, wherein a pressure build-up in the control chamber 3 by an inlet throttle element 4, a pressure relief of the control chamber 3, however, by an operable outlet throttle 7 takes place. The outlet throttle 7 is closed by means of a closing body 8, the by a shaped body 10 in the embodiment of the solution according to the invention is taken to Figure 5 on a one-piece anchor 45. Above the one-piece configured armature 45 is an electromagnet 19 of the solenoid valve 18 comprising a magnet sleeve 20 resting on a dial 21 on the armature guide 41 is supported: On the outside of the injector body 1 is analogous to the stand The technique known variant provided an external thread on which a magnetic clamping nut is screwed on. By means of the magnetic clamping nut is the magnetic sleeve 20, which encloses the electromagnet 19 of the solenoid valve 18, on the injector body 1 attached.

The one-piece armature 45 is through a the electromagnet 19 in a central bore passing valve spring 17 acted upon. The one-piece anchor 45 includes an anchor plate 45.1, which merges in this anchor design in a bolt section 45.2. Of the bolt-shaped extending portion 45.2 of the integrally configured armature 45 is enclosed by a clamped in the injector 1 recorded anchor guide 41. The armature guide 41 may be provided with longitudinal grooves 42 and 43, which the guide portions represent in which the one-piece configured anchor 45 when actuated through the solenoid valve 18 in the injector body 1 in the vertical direction up and down is.

At the bottom of the armature guide 41 is a stop surface in the form of a groove 47th educated. This groove 47 serves as a stop surface for a like a bayonet closure formed on the bolt-shaped portion 45.2 of the one-piece armature 45 flattening 46. Below the flattening 46 is the already mentioned shaped body 10, the closing body 8, with which the outlet throttle 7 of the control chamber 3 is closed will, surround.

The one-piece anchor 45 shown in Figure 5 is with the surrounding anchor guide 41 joined such that first the one-piece armature 45 is rotated so that the flattening 46 to the bore of the armature guide 41 is aligned, which is formed in a rotational position is that the armature guide 41 is pushed onto the bolt part 45.2 of the one-piece armature 45 can be. After pushing the armature guide 41 is rotated until the flattening 46 engages in the stop surface 47 formed on the armature guide.

An anti-rotation according to this embodiment of a one-piece armature 45 is given that the depth of the stop surface 47 in the lower region of the armature guide 41 sized larger than the stroke, the one-piece configured anchor 45 in the armature guide 41 exerts upon actuation of the solenoid valve 18. This will get the Flattening 46 in no operating state out of engagement with the bottom of the Anchor guide 41 formed stop surface 47th

For completeness, it should be mentioned that the inlet throttle 4, which the control room. 3 in the interior of the injector body 1 with control volume applied, via an obliquely in the Injector body 1 opening fuel supply is acted upon, in which a filter element is admitted.

The illustration according to FIG. 6.1 shows a slotted anchor plate.

The illustrated in Figure 6.1 anchor plate 36 is at its periphery with one or more triangular recesses 39 provided at its radially on the symmetry line the anchor plate 36 tapered end are provided with a slot 40 (see. Representation according to Figure 3).

From the illustration according to FIG. 6.3, the top view of the anchor plate 36 is shown in FIG Figure 6.1. The anchor plate 36 includes a bore 37, which has a slot-shaped Opening 48 expires in the triangular recess 39. A first contact surface 49 and a second contact surface 50 of the slot-shaped recess 48th are dimensioned so that the distance to each other is less than the diameter of the bore 37. The two remaining, formed on the circumference of the anchor plate 36 triangular Recesses 39 are in their bore 37 respectively facing side also provided with slots 40, analogous to the representation of the anchor plate 36 according to the figure 3.2.

Figure 6.2 shows the detailed representation of a pre-assembled anchor group.

According to this embodiment of the solution according to the invention, the anchor bolt 30 in the area in which he enclosed by joining with the anchor plate 36 of this is, a first diameter, the diameter of the bore 37 of the anchor plate 36 corresponds. This diameter is in the lower region of the anchor bolt 30 in a Area of tapered diameter about. In this area will be tapered diameter when mounting the armature assembly first provided with the slot 48 anchor plate 36 pushed and then upwards towards the stop 31 of the anchor bolt 30 attached to this, pushed. This assembly step is followed by assembly the armature guide 41, which is configured in its lower region with a groove 47 as a groove Stop surface is provided. The anchor guide becomes like a bayonet catch 41 initially rotated on the anchor bolt 30 with the stop surface 46 in alignment. Then done a sliding of the armature guide 41 to the region of tapered diameter of the anchor bolt 30th

At the anchor guide 41, which is the area of tapered diameter of the anchor bolt 30, inner guide portions 52 are formed.

With the bayonet locking solution shown in Figure 6.2 for joining anchor plate 36, anchor bolt 30 and anchor guide 41 can prevent rotation of this preassembled Assembly without additional security elements done. It's just for that Take care - for example, by installing a biasing element between anchor plate 36 and end face of the armature guide 41 - that the flattening 46 always in contact the wall of the lower groove 47 is held on the armature guide 41. By means of the spring element 14, the components 36 and 41 may be designated at a reference numeral 15 Distance at the anchor bolt 30 are held apart.

FIG. 6.4 shows the section A-A according to the illustration in FIG. 6.2.

From this representation, it is apparent that the armature guide 41 is formed on its inner guide Inner groove sections 53 includes. When mounting the anchor bolt 30 this is so turned that its abutment surface 35 through the Innennutabschnitte 53 of the armature guide 41 can be performed. Thereafter, a rotation of the anchor bolt 30 takes place such that the abutment surface 35 with formed thereon flattening 46 by about 90 ° according to the Representation in Figure 6.4 to the inner guide portions 53 rotates. The flats 46 the abutment surface 35 thus abut against the lower groove 47 of the armature guide 41.

Figure 6.5 shows the anchor bolt 30 formed thereon approach 31 in a comparison to its mounted position in Figure 6.2 rotated by 90 ° position. Compared to the position of the anchor bolt 30 shown in Figure 6.2 is this in the illustration according to Figure 6.5 is rotated such that the flats 46 on the stop surface 35 perpendicular to the drawing level. In this position, the anchor bolt is included with it Anchor plate 36 through the inner guide portions 53 of the armature guide 41st feasible and therefore mountable. Since the groove depth of the lower groove 47 is sized larger than the stroke of the mounted anchor group, is always an anti-rotation during operation the anchor bolt relative to the anchor guide ensured.

Claims (10)

1. Solenoid valve for a fuel injector for injecting fuel into the combustion chamber of an internal combustion engine, having an injector body (1) which comprises an electromagnet (19), using which an armature group of the solenoid valve (18) can be actuated for the pressure relief of a control space (3), by means of which a nozzle needle/plunger arrangement (2) in the injector body (1) can be moved and the armature group comprises a first armature part and a second armature part, characterized in that the armature group comprises a plate-shaped armature part (36, 45.1) and a pin-shaped armature part (30, 45.2) which are joined to one another by a plugin/rotational connection (31, 38; 47).
2. Solenoid valve according to Claim 1, characterized in that one of the armature parts (30, 45.2; 36, 45.1) is surrounded by an armature guide (41) having guides (42, 43; 52), and the armature guide (41) comprises guide sections (42, 43; 52) which extend in the longitudinal direction of the pin-shaped armature part (30, 45.2).
3. Solenoid valve according to Claim 2, characterized in that the guide sections (42, 43; 52) on the armature guide (41) are configured as longitudinal grooves.
4. Solenoid valve according to Claim 1, characterized in that the pin-shaped armature part (30, 45.2) T has a stop face (35, 46) on its end which faces the control space (3).
5. Solenoid valve according to Claim 1, characterized in that the armature group (30, 45.1; 36, 45.2) is acted on in the closing direction by a valve spring (17) and comprises a shaped body (10) at the end which faces the control space (3), which shaped body (10) engages around a closing body (8).
6. Solenoid valve according to Claim 1, characterized in that a projection (31) with projection faces (32) is formed on the pin-shaped armature part (30) of a two-part armature (30, 36).
7. Solenoid valve according to Claim 6, characterized in that an opening (38) which corresponds to the shape of the projection (31) is configured on the plate-shaped armature part (36) of the two-part armature (30, 36).
8. Solenoid valve according to Claim 7, characterized in that the pin-shaped armature part (30) and the plate-shaped armature part (36) of the two-part armature (30, 36) are secured by an anti-rotation safeguard (44) which penetrates the opening (38) and is accommodated in a guide (42, 43) of the armature guide (41).
9. Solenoid valve according to Claim 1, characterized in that the pin-shaped armature part (30) has a section with a smaller diameter, which section corresponds to the spacing between a first and a second bearing face (49, 50) of an opening (48) in the plate-shaped armature part (36).
10. Solenoid valve according to Claim 9, characterized in that a connection in the form of a bayonet closure (51) is formed between the groove (47) of the armature guide (41) and the flattened section (46) of the first pin-shaped armature part (30) in the case of two-part armatures (30, 36).

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