DE102020100623A1 - Assembly for a variable valve train - Google Patents

Abstract

An assembly (1) for a variable valve drive is proposed, which assembly (1) consists of a central thrust plate (2) with spring tongues (3), the assembly (1) having an e-actuator (5) positioned orthogonally to the thrust plate (2) ), the push rod (6) of which forms an angular drive (8) with a slide (7) running parallel to the thrust plate (2), which slide (7) at its end (9) onto a driver surface (10) of the thrust plate (2) acts to move it in one direction, which displacement causes an inward displacement of the coupling slides in their cam follower levers when the e-actuator (5) is energized, with a compression spring (12) for the assembly (1) to move the thrust plate (2) back into its basic position when de-energized e-actuator (5) belongs, in which rearward displacement takes place at the same time an outward displacement of the coupling slides from the cam follower levers, the e-actuator (5) being on a length section (13) of the thrust plate (2) which is at least one large part of the spring tongues (3), seen in the direction of displacement of the thrust plate (2) when the actuator is energized, lies behind them and the angular drive (8) is a sliding drive.

Description

The invention relates to an assembly for a variable valve drive, system e-Rocker, of an internal combustion engine, which assembly consists of a central thrust plate which can be guided along a cylinder head of the internal combustion engine and has spring tongues depending therefrom, each of which is provided for an external application of a coupling slide of a switchable cam follower lever The assembly also has an e-actuator positioned orthogonally to the thrust plate and fixed to the internal combustion engine via its housing, the push rod of which extends its anchor rod and forms an angle drive with a slide running parallel to the thrust plate, which slide at its free end onto a driver surface of the thrust plate acts to move it in one direction, which displacement causes an inward displacement of the coupling slides in their cam follower levers when the e-actuator is energized, with a compression spring for return displacement to the assembly of the thrust plate in its basic position when the e-actuator is de-energized, during which backward displacement, the coupling slides are simultaneously shifted outward from the cam follower levers.

A generic assembly for an e-rocker valve train goes from the unpublished DE 10 2019 104 786.2 emerged. The e-actuator positioned orthogonally to the thrust plate sits at one end of the thrust plate, which end is in front of the spring tongues, seen in the direction of displacement of the thrust plate when the actuator is energized. To move the thrust plate back when the e-actuator is inactive or switched to low current, a compression spring acts on the other end of the thrust plate on an upturned tab of the latter (not shown).

Another e-rocker valve train is disclosed by the DE 10 2017 101 792 B4 . Its e-actuator sits at one end of the thrust plate and runs parallel to it. At this end, the thrust plate has a tab against which a push rod of the armature of the e-actuator acts.

The task is to create an assembly for a variable valve train, the e-Rocker system, that is stiffer and works more safely.

According to the invention, this object is achieved in that the e-actuator is arranged on a longitudinal section of the thrust plate, which lies behind the latter at least in the case of a large part of the spring tongues, seen in the direction of displacement of the thrust plate when the actuator is energized, the angle drive being a sliding drive with a locking groove curve on the Push rod or the slide and a locking pin on the respective other of the aforementioned elements, the push rod being guided in an axial bore of a sleeve attached to the housing of the e-actuator, which axial bore is cut by a transverse bore in the sleeve with the slide, the Compression spring envelops the push rod on the actuator side and is clamped between an annular shoulder of an actuator-side diameter expansion of the axial bore and a collar of the push rod and the slide at one end at the driver surface of the thrust plate via a coupling with the thrust plate that is effective in both directions of displacement of the thrust plate Schubblech is forcibly connected.

By now positioning the e-actuator in relation to the thrust plate, which thrust plate can also be a rod or the like, "behind" at least a large part or behind all of the spring tongues, when the actuator is applied to the thrust plate for the purpose of a simultaneous displacement of the coupling piston in the gear lever and the thrust plate are now “pulled” instead of “pressed”. This measure effectively prevents bending or undulating deformation of the thrust plate when the actuator is applied.

At the same time, due to this arrangement, the play resulting from the thermal expansion (aluminum cylinder head and steel thrust plate) is reduced, whereby, as a person skilled in the art can easily imagine, an optimal play reduction would exist with a central arrangement of the actuator to the thrust plate.

The proposed sliding drive with, for example, S-like locking groove curve and locking pin represents an excellent forced deflection of the actuator force. A special feature of the invention is also the space-saving attachment of the return pressure spring to the actuator, more precisely the installation in its thrust-side sleeve for guiding the push rod and its action on the push rod in the return direction. If necessary, the sleeve can also be dispensed with if the guidance would take place, for example, directly through the actuator.

In addition, the forced, form-fitting coupling of the slide with the thrust plate precludes "free-flight phases" of the thrust plate in the event of extreme mass accelerations resulting from driving operation. On-board diagnostic systems can now very reliably infer from the retracted basic position of the armature (de-energized / weakly energized) to the basic position of the slide bar (coupling slider not activated).

According to a further development of the invention, an annular groove-collar connection of the slide to the thrust plate is proposed for the forced coupling. So For example, the slide can have an annular groove in the section of its free end, into which a spring collar of a tab or another component of the thrust plate engages for connection. The slide could also have a single or double ring collar which engages with corresponding projections on the thrust plate. If necessary, claw-like or hook-like solutions, or screw, rivet, adhesive, welded or clamped connections or the like are also conceivable.

According to a specification of the invention, a short and therefore comparatively stiff tab, for example, connected in one piece, as above, stands from the thrust plate. for a fixed connection with the slide. The tab can also be a component that is joined separately to the thrust plate.

As an alternative to this, it is proposed to dispense with the tab and to position the actuator in such a way that the slide lies in a pocket of the slide plate, in alignment therewith. This is a further contribution to a comparatively stiff, space-saving and quickly reacting assembly.

Due to the orthogonal adjustment of the e-actuator to the push bar, the accidental mass accelerations resulting from driving no longer lead to the summation of the inertia of the armature with the push rod and the push plate. This significantly reduces the likelihood of inadvertent actuation of the assembly. Of course, the e-actuator can also be positioned “at an angle” or “from below” on the thrust plate and the spring tongues can also protrude "upwards" from the thrust plate.

Finally, according to a further development of the invention, the thrust plate should, for example, be formed in one piece with the spring tongues. The spring tongues can be generated from the thrust plate using punching and bending technology and, if necessary, also separately protected against wear (heat treatment, applied layers). There is also provision for separately prefabricated spring tongues to be joined to the thrust plate (welding, riveting, gluing, clinching, etc. or a combination of these). If necessary, a form-fitting fastening of the spring tongues is also possible. It would also be possible to represent the spring tongues only as largely stiff fingers.

The proposed construction can, for example, be applied to a cylinder bank of an internal combustion engine on the exhaust valve side for cylinder deactivation. Use on the inlet valve side or on both sides is equally conceivable. In addition to cylinder deactivation, valve lift switchover is also an option.

• • 1 zeigt in einer räumlichen Ansicht die e-Rocker-Baugruppe ohne schaltbare Nockenfolger;
• • 2 zeigt in einer Detaillierung den e-Aktor mit nachgeschaltetem Winkeltrieb;
• • 3 zeigt die Baugruppe in einem Ausschnitt um den e-Aktor und
• • 4 zeigt in einem Ausschnitt eine alternative Anbindung des Schubblechs an den e-Aktor.

To the drawing:

• • 1 shows a three-dimensional view of the e-rocker assembly without switchable cam followers;
• • 2 shows in detail the e-actuator with a downstream angle drive;
• • 3 shows the assembly in a section around the e-actuator and
• • 4th shows a section of an alternative connection of the thrust plate to the e-actuator.

Out 1 is the general structure of the e-rocker assembly 1 emerged. The assembly 1 can be delivered pre-assembled to the cylinder head of the internal combustion engine and fastened there. However, it is also conceivable to use the e-actuator 5 , with or without the angle drive explained below 8th to be installed separately. For fastening the e-actuator 5 an in 2 With " 26th “Labeled tab, which is from a lower face of a housing 4th of the e-actuator 5 stands away.

The assembly 1 consists (see further figures) of a central thrust plate that can be guided along the cylinder head 2 with one-piece dependent spring tongues 3 , each of which is provided for an external front-side loading of a transverse coupling slide (not shown) or a transverse coupling slide assembly of a switchable cam follower lever (rocker arm). Important component of the assembly 1 is still the longitudinal space-saving orthogonal to the thrust plate 2 employed, aforementioned e-actuator 5 . Its anchor 26th is via an anchor rod 11 out of the case 4th out through a push rod 6th extended with a parallel to the thrust plate 2 running, pin-like slide 7th an angle drive 8th (Schiebuttrieb) forms. The push rod 6th has an S-like locking curve that is remote from the actuator 14th coming from an end face of the push rod 6th goes out. In the locking curve 14th a locking pin engages 15th a slide 7th a (s. 2 ). The latter includes the push rod like a fork 6th .

The aforementioned slide 7th which, how from 3 can be seen in a cross hole 17th one the push rod 6th housing as well as on the housing 4th of the e-actuator 5 attached sleeve 19th runs, works at its one end drawn on the left 9 on a driving surface 10 of the thrust plate 2 a. The driving surface 10 lies as one piece from the thrust plate 2 upright flap 22nd in front. As you can see, the slide runs 7th parallel to and just above the thrust plate 2 . It is via a form fit connection 23 with the tab-like driving surface 10 of the thrust plate 2 coupled. More precisely, the slider has 7th an annular groove into which a bore-like collar of the tab 22nd intervenes.

The assembly also counts 1 another the push rod 6th in the upper section comprehensive compression spring 12th . This acts at one end (on the actuator side) against a collar 21 the push rod 6th . At the other end is the compression spring 12th on a ring shoulder of an enlarged diameter 20th an axial bore 16 the sleeve 19th supported which axial bore 16 the push rod 6th in its lower section with the locking curve 14th leads. The e-actuator 5 stands according to the solution after the 1 - 3 with the sleeve 19th on the front side immediately above the thrust plate 2 .

According to the variant after 4th protrudes the sleeve 19th slightly in an elongated recess 25th of the thrust plate 2 . The slider 7th of the angle drive 8th lies in the course of the thrust plate 2 . It works with its free end 9 against a transverse forehead 24 of the thrust plate 2 . The aforementioned form-fit connection is also located in this area 23 in front.

How out 1 the e-actuator is removable 5 with a "rear" length section 13th of the thrust plate 2 arranged, which is an important part of this design. At this length 13th there are only two spring tongues left 3 , in the direction of displacement of the thrust plate 2 seen when the actuator is energized, behind the e-actuator 5 . Each of the spring tongues 3 serves here to act on an outer face of a cross coupling slide in a switchable rocker arm.

In the case of a desired simultaneous displacement of the coupling slides of the rocker arm (e.g. exhaust valve deactivation), the e-actuator 5 energized. Its anchor 26th with anchor rod 11 moves the attached push rod 6th orthogonally to the sliding plate 2 to. About the angle drive described above 8th the forcibly relocates with the thrust plate 2 coupled slider 7th the sliding plate 2 to the left in the drawing (s. 1 ). Much of the thrust plate 2 (to the right of the e-actuator 5 ) is "pulled" instead of "pressed", as in St. d. T. to be recorded.

A provision of the thrust plate 2 (Basic position) for the purpose of shifting the coupling slides backwards takes place when the e-actuator is de-energized 5 . The angle drive 8th moves back here. This pulls on the push rod 6th acting compression spring 12th the sliding plate 2 in its basic position (here to the right). A (retracted) basic position of the anchor 26th of the e-actuator 5 certainly corresponds to the basic position of the thrust plate 2 (Keyword "OBD").

List of reference symbols

1)

module

2)

Thrust plate

3)

Spring tongue

4)

casing

5)

e-actuator

6)

Push rod

7)

Slider

8th)

Angle drive

9)

end

10)

Driving surface

11)

Anchor rod

12)

Compression spring

13)

Length section

14)

Detent curve

15)

Locking pin

16)

Axial bore

17)

Cross hole

18)

Ring heel

19)

Sleeve

20)

Diameter expansion

21)

collar

22)

Tab

23)

Form-fit connection

24)

Transverse forehead

25)

Recess

26)

anchor

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102019104786 [0002]
• DE 102017101792 B4 [0003]

Claims (6)

Assembly (1) for a variable valve train, system e-Rocker, of an internal combustion engine, which assembly (1) consists of a central thrust plate (2) which can be guided along a cylinder head of the internal combustion engine and which has spring tongues (3) depending therefrom, each of which for one A coupling slide of a switchable cam follower lever is provided on the outer face side, the assembly (1) also having an e-actuator (5) which is positioned orthogonally to the thrust plate (2) and which can be fixed to the internal combustion engine via its housing (4) and whose anchor rod (11 ) extending push rod (6) with a slide (7) running parallel to the thrust plate (2) forms an angle drive (8), which slide (7) at its free end (9) towards a driver surface (10) of the thrust plate (2) whose displacement acts in one direction, which displacement causes an inward displacement of the coupling slides in their cam follower levers when the e-actuator (5) is energized, with the assembly (1) also includes a compression spring (12) for moving the thrust plate (2) back into its basic position when the e-actuator (5) is de-energized, during which rearward displacement the coupling slides are simultaneously shifted outward from the cam follower levers, characterized in that the e-actuator (5) is arranged on a length section (13) of the thrust plate (2), which lies behind the latter at least in the case of a large part of the spring tongues (3), seen in the direction of displacement of the thrust plate (2) when the actuator is energized, the angular drive (8) being a Slide drive with a locking groove cam (14) on the push rod (6) or the slide (7) and a locking pin (15) on the respective other of the aforementioned elements, the push rod (6) in an axial bore (16) on the housing ( 4) of the e-actuator (5) attached sleeve (19) is guided, which axial bore (16) is cut from a transverse bore (17) in the sleeve (19) with the slide (7), the compression spring (12) the Push rod (6) a Enclosed on the actuator side and clamped between an annular shoulder (18) of an actuator-side diameter expansion (20) of the axial bore (16) and a collar (21) of the push rod (6) and the slide (7) at one end (9) at the driver surface (10) of the thrust plate (2) is positively connected to the thrust plate (2) via a coupling which is effective in both directions of displacement of the thrust plate (2). Assembly according to Claim 1 , characterized in that the driver surface (10) for the slide (7) is a tab (22) protruding from the thrust plate (2). Assembly according to Claim 2 , characterized in that the tab (22) is a bent material section of the thrust plate (2). Assembly according to Claim 1 , characterized in that the driver surface (10) for the slide (7) is a transverse face (24) of a recess (25) of the thrust plate (2), into which recess (25) the sleeve (19) of the e-actuator (5 ) protrudes, wherein the slide (7) lies in the course of the thrust plate (2) and acts with its free end (9) on the transverse face (24). Assembly according to Claim 1 , 2 or 4th , characterized in that for the positive connection of the slide (7) to the thrust plate (2) a form-fit connection (23) present between these components (7, 2), such as an annular groove-collar connection, is applied. Assembly according to Claim 1 , characterized in that the spring tongues (3) are either an integral part of the thrust plate (2) or are joined to it separately.

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