EP2636860B1 - Device for camshaft adjustment in an internal combustion engine - Google Patents

Description

The present invention relates to a device for adjusting the camshaft of an internal combustion engine according to the preamble of the main claim. Furthermore, the present invention relates to a method for camshaft adjustment, in particular method for operating such a generic device.

Such a device is from the DE 196 11 641 C1 known. This document describes the background and context of the invention, including the constructive realization of the camshaft, their storage and their interaction with the internal combustion engine, which is not discussed in detail in the present application.

Specifically, this known device according to the preamble describes how an actuating element (plunger or actuating pin) by cooperation with a cam associated Hubprofil can cause an axial, predetermined adjustment of the camshaft, such as the purpose of offering a cam different cam tracks switchable.

The known device typically requires several plungers (confirmation pins), such as the FIG. 2 of the DE 196 11 641 C1 , it can be seen, so that, depending on the axial displacement position of the Hubprofilanordnung, each engage a suitably opposing pin and can cause the respective intended axial displacement. This is structurally complex and requires a corresponding amount of installation space at the site.

The publication DE10148177A1 contains the closest prior art and discloses all features of the preamble of the first claim.

Object of the present invention is to simplify a controlled by plunger, superordinate device constructive, in particular the provision of multiple, axially spaced ram (actuation pins) to make unnecessary and to increase operational safety and ease of maintenance.

The object is achieved by the device having the features of the main claim and the independent method claim. Advantageous developments of the invention are described in the subclaims.

Advantageously according to the invention, the two different penetration depths according to the invention (in combination with a multi-part tappet) make it possible to provide the tappet unit at a (single) axial mounting location, which, depending on the set activation (penetration depth and / or width of the engagement portion of the tappet), Accordingly, the control grooves (grooves) can selectively select and depart, which then the intended respective axial displacement of the camshaft is effected upon rotation of the Hubprofilelements.

According to the invention, the first and second control grooves are designed so that the camshaft can be adjusted by means of the first axial movement and the second axial movement from a starting position to a first axially displaced position and back to the starting position by the action of the plunger unit controlling the control unit, and the Hubprofilelement a third control groove adjacent and / or partially overlapping with the first and the second control groove and the third control groove describes a third axial movement of the camshaft, wherein the third control groove is formed and / or arranged such that by the action of the plunger unit controlling the control camshaft from the starting position or the first axially displaced position in a second axially displaced position, which is different from the starting position and the first axially displaced position, can be moved.

In preferred embodiments, the plunger is designed in several parts by means of plunger elements (inner / outer plunger) guided into one another, advantageously in accordance with the invention in conjunction with an associated electromagnetic adjustment device which assigns each plunger to an armature unit which is preferably driven or moved separately from one another.

Fig. 1 bis Fig. 4:

verschiedene perspektivische bzw. seitliche Ansichten eines Hubprofilelementes, gemäß einer ersten Ausführungsform der Erfindung wie es zum Bewirken der Nockenwellenverstellung an bzw. auf einer Nockenwelle drehfest vorgesehen sein kann;

Fig. 5 bis Fig. 7:

vier mögliche Stellvorgänge, wie sie im ersten Ausführungsbeispiel der vorliegenden Erfindung möglich sind, in der Form einer abgewickelt gezeigten Nutenführung im Hubprofilelement der Fig. 1 bis 4;

Fig. 9 bis Fig. 11:

Längsschnitte durch eine elektromagnetische Stellvorrichtung, welche endseitig einen mehrgeteilten Stößel zur Realisierung der Stößeleinheit ausbildet.

Further advantages, features and details of the invention will become apparent from the following brief description of the embodiments and from the drawings; these show in

Fig. 1 to Fig. 4:

various perspective or side views of a Hubprofilelementes, according to a first embodiment of the invention as it may be provided for effecting the camshaft adjustment on or on a camshaft rotatably;

Fig. 5 to Fig. 7:

four possible adjusting operations, as are possible in the first embodiment of the present invention, in the form of a disclosed Nutenführung in Hubprofilelement the Fig. 1 to 4 ;

FIGS. 9 to 11:

Longitudinal sections through an electromagnetic actuator which forms a multi-part ram end to implement the ram unit.

Figures 1 to 4 illustrate how the control grooves (in the manner of webs) in the Hubprofilelement shown (cam piece) run; as in this context, in particular the FIGS. 9 to 11 can recognize, the ram unit has a (a narrow engaging portion 11 forming) inner plunger 10 and a surrounding sleeve-shaped outer plunger 12, wherein, in the manner to be described below, both plungers are actuated independently by electromagnetic control independently. The inner tappet makes it possible to realize a greater penetration depth (in conjunction with a narrower groove profile, Figure 3 . 4 ), the wider outer tappet (hollow tappet) can not fully penetrate into the depth of such a narrow bottom region forming groove.

Advantageously according to the invention, the present invention makes it possible by means of an example in the Fig. 9 to 11 shown two-piece ram unit to realize a total of relative movement (axial displacement) of the Hubprofilelementes between three positions (with the effect that a single - multi-part - ram unit must be mounted and accordingly no additional axial installation space with corresponding additional effort is needed).

The settlements of the Fig. 5 to 8 The respective Nutenbahnverläufe (control grooves) are symbolized by thick black bars or bar sections (ie wide groove) and dashed / dotted Nutenbahnverläufe (narrow groove), deepened in overlapping even within a wide groove narrow groove. Furthermore, the two-part pestle is symbolized by a black dot ( Fig. 1 . Fig. 8 , Activation by the inner tappet), and a circle or ring as a symbol ( Fig. 6 . Fig. 7 ), corresponding to the sleeve-shaped hollow or outer plunger.

The Fig. 5 illustrates first how, as shown by engagement of the extended inner tappet 10 in the deep groove shown (arrow 20 of the Fig. 5 ) a right shift of the scenery is effected, up to the position of Fig. 6 (The plunger position remains unchanged in all examples). In the position of Fig. 6 For example, with the purpose of returning to a home position (center position), the outer tappet would describe the broad groove track described with arrows 22, so that then the backdrop shown is moved from the right position back to the basic position (center position).

Fig. 7 then shows how a left shift is effected from the middle position, by means of the outer sleeve; Fig. 8 illustrates the reset from the left position to the basic position (center position) by means of inner tappets. The groove or track courses of Fig. 5 to 8 Insofar serve to further clarify the structural design of the Hubprofilelements according to embodiment of the Fig. 1 to 4 ,

The Fig. 9 to 11 show in schematic form the constructive realization of the actuator as an electromagnetic actuator with two anchors; an inner tappet (anchor) 10, which has a permanent magnet 14 for cooperation with a (stationary) core 13, and a second armature 12a, which merges into the hollow tappet.

By energizing a coil II (reference numeral 16), the flat armature 12a (thus the hollow tappet 12) is moved downward. The permanent magnet 14 of the inner tappet 10, however, ensures that in this operation, the inner tappet on the core 13 and thus in the in Fig. 9 shown, retracted position remains.

Fig. 10 shows the hollow rams extended in this way; a mark "X" of one of the coils symbolizes the energized state.

To extend the inner tappet, the permanent magnet has to be wound by a coil I (reference 18) (surrounding the core 13). be repelled (with appropriate energization of the coil I). In this case, the hollow tappet (by means of the flat armature) is automatically pulled in the plane of the drawing up, so that the hollow tappet can not be extended, it results in the operating condition of Figure 11 ,

Claims (11)

1. A device for camshaft adjustment of an internal combustion engine with
   a lifting profile element, offering a control groove, and which is provided in a rotationally fixed manner on or against an axially displaceably mounted camshaft,
   and a control unit for generating a predetermined axial displacement of the camshaft, wherein the control unit has a tappet unit (10, 12) preferably movable radially with respect to the camshaft, constructed for controllable engagement into the lifting profile element,
   wherein the lifting profile element forms a first control groove (20) which is constructed for cooperating with the tappet unit (10, 12) in a first penetration depth to describe a first axial movement of the camshaft and wherein
   the lifting profile element forms a second control groove (22),
   characterized in that this second control groove (22) is constructed for cooperating with the tappet unit (10, 12) in a second penetration depth, different from the first penetration depth, to describe a second axial movement of the camshaft different from the first axial movement, the first (20) and the second (22) control groove are constructed so that by action of the control unit actuating the tappet unit (10, 12), the camshaft can be moved by means of the first axial movement and of the second axial movement from an initial position into a first axially displaced position and back into the initial position, and the lifting profile element has a third control groove adjacent to and/or partially overlapping with the first (20) and the second (22) control groove, and the third control groove describes a third axial movement of the camshaft,
   wherein the third control groove is constructed and/or arranged so that by the action of the control unit actuating the tappet unit (10, 12), the camshaft can be moved from the initial position or from the first axially displaced position into a second axially displaced position, which is different from the initial position and from the first axially displaced position.
2. The device according to claim 1, characterized in that the first (20) and the second (22) control groove are provided adjacent to one another in a lifting profile element which is shared and/or is constructed in one piece.
3. The device according to claim 1 or 2, characterized in that the first (20) and the second (22) control groove in the lifting profile element continue into one another at least partially.
4. The device according to one of claims 1 to 3, characterized in that the tappet unit (10, 12) is constructed so that the tappet unit is able to be switched between the first and the second penetration depth for engaging into the first (20) and the second (22) control groove on the engagement side, and/or is able to be adjusted or switched for forming an engagement section which is changeable in width.
5. The device according to one of claims 1 to 4, characterized in that the tappet unit (10, 12) has on the engagement side an arrangement with an inner tappet (10) and with a sleeve-like outer tappet (12) preferably concentrically surrounding the inner tappet.
6. The device according to claim 5, characterized in that the inner tappet (10) and the outer tappet (12) are associated with the first (20) or respectively the second control groove and/or with the first or respectively the second penetration depth.
7. The device according to claim 5 or 6, characterized in that the inner tappet (10) and the outer tappet (12) are constructed so as to be actuatable and/or operable independently of one another.
8. The device according to one of claims 1 to 7, characterized in that the first (20), second (22) and third control groove are constructed so that through the action of the control unit controlling the tappet unit (10, 12), the camshaft be moved arbitrarily between three axial displacement positions which are different from one another.
9. The device according to one of claims 1 to 8, characterized in that the tappet unit (10, 12) is driven by means of an electromagnetic operating device, wherein the tappet unit cooperates with an armature unit of the electromagnetic operating device which is movable as a reaction to a current feed of a preferably stationary coil unit.
10. The device according to claim 9, characterized in that the armature unit is constructed in multiple parts with a first and a second armature corresponding to a tappet unit which is realized in several parts so as to be actuatable independently of one another.
11. The device according to claim 10, characterized in that one of the armatures has a permanent magnet unit for cooperation with a preferably stationary core unit, which permanent magnet unit is arranged so that as a reaction to a movement of the other armature the permanent magnet prevents the moving of the one armature.

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