阅读说明：本技术 用于可变气门机构的促动装置和用于制造操纵单元的方法 (Actuating device for a variable valve train and method for producing an actuating unit ) 是由 D·肖特 H·埃伦特 于 2019-09-12 设计创作，主要内容包括：本发明涉及一种用于内燃机的可变气门机构的促动装置,所述促动装置具有能沿着纵轴线(1)移动的推移元件(4)并且具有多个能随着所述推移元件移动的传递元件(5),为了分别轴向地操纵至少一个能切换的气门机构部件,所述传递元件以预确定的间距(L)轴向相继地布置并且在所述推移元件(4)上横向于所述纵轴线(1)以具有预确定的长度(L<Sub>A</Sub>)的自由端部伸出,所述长度大于轴向的所述间距(L),其中,所述推移元件(4)和所述传递元件(5)一件式地实施为操纵单元(2)。本发明还涉及一种用于制造操纵单元的方法,所述操纵单元用于内燃机的可变气门机构的促动装置。(The invention relates to an actuating device for a variable valve train of an internal combustion engine, comprising a sliding element (4) that can be moved along a longitudinal axis (1) and comprising a plurality of transmission elements (5) that can be moved with the sliding element, which are arranged axially one after the other at a predetermined distance (L) and are arranged on the sliding element (4) transversely to the longitudinal axis (1) to have a predetermined length (L) in order to actuate at least one switchable valve train component in each case axially A ) Is greater than the axial distance (L), wherein the pusher element (4) and the transmission element (5) are embodied in one piece as a handling elementA unit (2). The invention also relates to a method for manufacturing an operating unit for an actuating device of a variable valve train of an internal combustion engine.)

1. An actuating device for a variable valve train of an internal combustion engine, having a sliding element (4) which can be moved along a longitudinal axis (1) and having a plurality of transmission elements (5) which can be moved with the sliding element and which are arranged axially one after the other at a predetermined distance (L) and which are arranged on the sliding element (4) transversely to the longitudinal axis (1) to have a predetermined length (L) in order to actuate at least one switchable valve train component in each case axially_A) Is larger than the axial distance (L), wherein the pusher element (4) and the transmission element (5) are embodied as a single piece as a handling unit (2).

2. Actuator device according to claim 1, wherein the steering unit (2) is manufactured from sheet material by stamping and bending.

3. Actuator device according to claim 1 or 2, wherein the steering unit (2) is manufactured by prototyping.

4. Actuating device according to one of claims 1 to 3, characterized in that the pusher element (4) is produced from a sheet metal material by stamping as a flat pusher strip, from which the transmission element (5) is stamped out as a leaf spring and bent with a free end projecting.

5. Actuator device according to any one of claims 1 to 4, wherein the push-moving element (4) is produced as a flat push-moving strip by prototyping and the transmission element (5) is produced as a leaf spring having a material thickness (S) which is reduced compared to the material thickness (S) of the push-moving strip (4).

6. Actuating device according to one of claims 1 to 5, characterized in that a handling module (3) is arranged in a region axially between two transmission elements (5) for transmitting an axial pushing movement onto the pushing element (4).

7. Actuating device according to claim 6, characterized in that the actuating module (3) is at least partially received in a slot (8) of the pusher element (4), which slot is axially delimited by two axially successively arranged transmission elements (5).

8. Actuating device according to claim 6 or 7, characterized in that the actuating module (3) has a reversing unit, by means of which a linear movement produced by a drive element perpendicular to the longitudinal axis (1) can be transmitted to the pusher element (4) as a pusher movement in the direction of the longitudinal axis (1).

9. Actuating device according to one of claims 6 to 8, characterized in that the pusher element (4) is movably passed through and supported by the handling module (3).

10. A method for producing an actuating unit for an actuating device of a variable valve train of an internal combustion engine, having a sliding element (4) which can be moved along a longitudinal axis (1) and having a plurality of transmission elements (5) which can be moved with the sliding element and which are used for axially actuating at least one associated switchable valve train component in each case, wherein the sliding element (4) is stamped from sheet metal into a sliding web from which two transmission elements (5) are stamped as leaf springs which are arranged axially one behind the other at a predetermined distance (L), wherein one of the leaf springs is stamped with a length which is increased by a predetermined additional length (Delta L) and is bent over with an additional web (14) having the additional length (Delta L), next, the two plate springs have the same length (L)_A) Is bent over the push bar in such a way that it projects.

Technical Field

The present invention relates to an actuating device for a variable valve train of an internal combustion engine of the type defined in detail in the preamble of claim 1 and to a method for manufacturing an actuating unit for an actuating device for a variable valve train of an internal combustion engine of the type defined in detail in the preamble of claim 10.

Background

A variable valve train of a piston engine is known from DE 102017101792 a 1. The valve travel can be selectively transmitted to at least one associated gas exchange valve by means of a switchable valve pressure lever via at least one primary cam and a secondary cam of the camshaft. The valve rod can be switched by means of a switching bolt and is connected to a rod-shaped connecting element, which in turn is coupled to the switching rod in an actuating connection. The switching lever is arranged parallel to the associated camshaft above the respective valve rod and can be moved longitudinally by means of a linear actuator against the restoring force of a spring element from a rest position into a switching position. However, there are the following problems here: a large axial installation length results due to the arrangement of the linear actuator and the spring element. Furthermore, the plurality of components requires complex manufacturing and assembly, which is time-consuming and expensive due to the required precise positioning.

Disclosure of Invention

The invention is therefore based on the object of configuring an actuating device of the type mentioned above in a manner that is simple and space-saving in terms of production and assembly. The object of the invention is, furthermore, to provide a handling unit for producing an actuating device of the aforementioned type.

This object is achieved by the features of claim 1 and alternatively by the features of claim 10. Further advantageous embodiments emerge from the respective dependent claims, the description and the drawings.

Here, an actuating device of a variable valve mechanism for an internal combustion engine is proposed. The actuating device comprises a sliding element which can be displaced along a longitudinal axis and a plurality of transmission elements which are movably connected to the sliding element. For actuating at least one switchable valve train component in each case, the transmission elements are arranged one after the other at predetermined axial distances on the pusher element and are erected with their free ends of predetermined length on the pusher element transversely to the longitudinal axis. According to the invention, the predetermined length of the transmission elements is greater than their respective axial spacing from one another. The pusher element and the transmission element are in this case produced as a single piece as the actuating unit. In this way, an actuating device with a reduced axial installation length is achieved, which saves installation space and, furthermore, by means of the one-piece embodiment, reduces the manufacturing and assembly outlay. At the same time, the position tolerance chain of the actuating device is shortened. In the case of mass production, the input for both types of machines, i.e. the machine for manufacturing the transfer element and the machine for assembling the parts, can be saved in this way.

The actuating unit can be produced in a particularly simple manner from sheet metal in a cost-effective manner by stamping and bending. The actuating unit can be stamped and bent out of a sheet blank having a constant material thickness.

In a further variant of the invention, the actuating unit is produced by prototyping. The actuating unit can be produced in one step in particular by die casting, injection molding or precision casting or by powder metal injection molding using a tool. In this way, a more precise production can be achieved in a simple manner compared to the bending method, whereby the tolerances of the entire actuating device can also be further reduced. Furthermore, the influence or damage of the material structure due to plastic deformation during the bending process is avoided and at the same time the safety against fatigue fracture is improved. Furthermore, high strength alloys that are not well suited for plastic bending processes may be used. Therefore, the safety against fatigue fracture can be further improved.

The transmission element is particularly advantageously embodied as elastic in the displacement direction of the displacement element, for example as a leaf spring. In this way, axial actuating movements can be transmitted without additional components in the unstressed corresponding cam base circle phase of the driven camshaft at different switching times of the valve train components by preloading the transmission element and individual switching of the valve train components. In this case, the switching process can already be initiated in a full stroke phase (Vollhubphase), in which the respective leaf spring is pretensioned, so that in the cam base circle phase an axial actuating movement is transmitted to the switching element of the valve train component, for example, the switching pin, by the respectively pretensioned leaf spring, and the switching element or the switching pin is displaced.

The actuating unit can be produced in a particularly simple manner in one piece when the push element is stamped from a sheet metal material into a flat push strip by stamping and the transmission element is stamped out of the push strip as a leaf spring and is bent at the free end on the push strip. The actuating unit can be stamped and bent out of the sheet metal blank. The spring rate of the leaf spring can be designed by the material thickness and/or the geometry or shape and size of the leaf spring.

Alternatively, the actuating unit with the flat push plate and the transmission element as a leaf spring can be produced in one piece by prototyping. In this case, the transfer element is preferably protoformed with a material thickness that is reduced compared to the material thickness of the sliding strip. The actuating unit can be produced particularly cost-effectively in one step, in particular by die casting, injection molding or precision casting or by powder metal injection molding with the aid of a tool. Here, the influence or damage of the material structure due to plastic deformation during the bending process is avoided and at the same time the safety against fatigue fracture is improved.

The leaf spring can be produced with a material thickness which is reduced by approximately a quarter compared to the material thickness of the sliding rail. Alternatively or additionally, the spring rate of the leaf spring can be designed by the geometry or shape and size of the leaf spring.

It is also conceivable to produce the actuating unit with the flat push plate and the transmission element as a leaf spring in one piece as a so-called 3D printing in a three-dimensional printing method.

In a particularly preferred embodiment of the invention, the sliding element is designed as a sliding bar with two transmission elements designed as leaf springs, which are each axially connected to at least one switchable valve train component for actuation with their free ends (abstehend) on the sliding bar with respect to the longitudinal axis.

In an advantageous embodiment of the invention, the actuating module is arranged in a space-saving manner in the region of the sliding element axially between the two transmission elements for transmitting an axial sliding movement to the sliding element.

The handling module can be received at least partially in the slot of the pusher element in a space-saving manner. In this case, the slot is preferably delimited axially by two transmission elements arranged one behind the other.

In a further preferred embodiment of the invention, the actuating module has a reversing unit, by means of which a linear movement generated by the drive element perpendicularly to the longitudinal axis can be transmitted to the pusher element as a pushing movement in the direction of the longitudinal axis.

In a further advantageous arrangement, which is particularly space-saving, the pusher element is movably passed through by the actuating module. In this case, the pusher element is preferably supported at the same time on the operating module. In this case, the pusher element is preferably guided between the deflection unit and a support connected to the deflection unit.

The object is also achieved by a method for producing an actuating unit for an actuating device of a variable valve train of an internal combustion engine, comprising a pusher element which can be moved along a longitudinal axis and a plurality of transmission elements which can be moved with the pusher element for axially actuating at least one associated switchable valve train component in each case, according to the invention, the pusher element is produced from a sheet metal Material by stamping as a pusher strip from which two transmission elements are stamped as leaf springs, which are arranged axially one behind the other at a predetermined distance, wherein one of the leaf springs is stamped to a length which is increased by a predetermined additional length and the web is bent over the additional length in an intermediate step.

The actuating device according to the invention can also be used in a particularly advantageous manner for actuating one or more switchable valve struts in a valve train of an internal combustion engine. It is also conceivable that the actuation device is used for actuating further switchable valve train components for a valve train lever, in particular at least one switchable cup tappet or roller tappet or at least one switchable supporting element.

Drawings

Further features of the invention emerge from the following description and the drawing, in which several exemplary embodiments of the invention are shown in a simplified manner. The attached drawings are as follows:

fig 1 shows in a first embodiment an actuating device for a variable valve mechanism of an internal combustion engine according to the present invention,

figure 2 shows the operating unit according to the invention of the actuating device in a separate view,

figure 3 shows an actuating device according to the invention in a second embodiment,

fig. 4 shows a handling unit according to the invention of the actuating device of fig. 3 in a separate view.

Detailed Description

Fig. 1 shows an actuator device for a variable valve mechanism of an internal combustion engine according to the present invention in a first embodiment. The actuating device has an actuating unit 2, which is movable along a longitudinal axis 1 and is designed in one piece, for actuating at least one switchable valve train component, not shown. Fig. 2 shows the actuating unit 2 of the actuating device in a separate view. The actuating module 3 is arranged in the region of the actuating unit 2 between the axial ends and serves to transmit an axial displacement movement to the actuating unit 2. The actuating unit has a pusher element 4 which can be moved along the longitudinal axis 1 and which carries two transmission elements 5 which are connected integrally to the actuating unit. The sliding element 4 is embodied as a flat sliding bar and is produced in one piece with a transmission element 5 as a leaf spring which is embodied so as to be elastically bendable in the sliding direction of the sliding bar. The leaf springs 5 can each transmit a sliding movement of the sliding strips 4 as an axial adjustment movement for switching the respectively associated valve train components.

The pusher plate 4 is designed as a flat bar having flat longitudinal sides 6 oriented transversely to the longitudinal axis 1, which are narrow in the material thickness direction, and wide longitudinal sides 7 oriented perpendicularly to these longitudinal sides. The leaf springs 5 are arranged one after the other in axial alignment at a predetermined distance L. The leaf spring is here arranged transversely to the longitudinal axis 1 so as to have a predetermined clear length L_AIs arranged projecting on the push bar 4, the clear length being greater than the axial distance L of the leaf springs 5 relative to one another. This makes it possible to significantly shorten the axial installation length of the actuating unit 2. A spacing L and a length L_AIn particular, the use conditions and the installation conditions are predefined.

The actuating unit 2 is produced in one piece by prototype molding, in particular by injection molding, die casting or precision casting or by metal powder injection molding. The push bar 4 and the leaf spring 5 can be produced in one production step by means of tools. The leaf spring 5 is designed to adapt the spring rate to the operating conditions with a corresponding spring geometry and with a reduced material thickness S compared to the material thickness S of the sliding rail 4. In this exemplary embodiment, the pusher plate 4 has a material thickness S of 2mm, while the leaf spring 5 is designed with a material thickness S of 1.5 mm.

The proportional relationship between the material thickness S of the leaf spring 5 and the material thickness S of the sliding strip 4 is not limited to one to four. Different proportionality relationships can be adapted to different conditions of use. It is also conceivable, for example, for the pusher plate 4 to have a material thickness S of 3mm, while the leaf spring 5 is embodied with a material thickness S of 1 mm. This results in a reduction of the material thickness of the leaf spring 5 by two thirds compared to the material thickness S of the sliding strip 4. The minimum material thickness is limited by the prototype or forming process.

The handling module 3 is designed in multiple parts and comprises a support section and a reversing unit with a housing 12. By means of the reversing unit, a linear movement generated by a drive element (not shown), in particular a displacement actuator or linear actuator, perpendicular to the longitudinal axis 1 can be transmitted to the displacement element 4 as a displacement movement in the direction of the longitudinal axis 1. The actuating module 3 is received with the support section partially into a slot 8 on the narrow longitudinal or material thickness side 6 of the push bar 4, which is located axially between the leaf springs 5 and is bounded axially by these leaf springs. The push bar 4 is inserted so as to be movable between the support section and the reversing unit or housing 12 in the region of the slot 8. The actuating module 3 and the sliding bar 4 can thus be supported via the support section on a stationary component of the internal combustion engine, in particular on a cylinder head of the internal combustion engine.

In the region of the slot 8, the push bar 4 has two openings 9, 10 on the wide longitudinal side 7, which are rectangular in plan view and are arranged one behind the other in the direction of the longitudinal axis 1. The actuating module 3 with the reversing unit engages with a 90 ° reversing lever, which is arranged in the housing 12 and is indicated, in a first opening 9 for transmitting the pushing movement to the pushing slats 4, which is narrow in the direction of the longitudinal axis 1 and wide transversely thereto. The reversing lever has two arms arranged at right angles to one another and is mounted pivotably about an axis 11 on a housing 12 of the drive element 3. One of the arms can be actuated perpendicularly to the longitudinal axis 1 by means of a linear movement that can be transmitted by a drive element, not shown, while the reversing lever engages with the other arm in a form-fitting manner in the first opening 9 of the sliding bar 4 in the sliding direction. A return spring, not shown, is arranged in the second opening 10, which extends with a large length in the direction of the longitudinal axis 1 and with a smaller length transversely thereto, said return spring being supported on one side in the opening 10 and on the other side on the housing 12. By actuating the drive element and pivoting the reversing lever, the push bar 4 can be moved out of the initial position against the spring force of a restoring spring, which restores the push bar 4 into the initial position after the end of the actuation.

In a second embodiment of the actuating device according to the invention in fig. 3 and 4, the actuating unit 2 is produced in one piece by stamping and bending, unlike the embodiment according to fig. 1 and 2. For this purpose, the push bar 4 is first produced from a sheet metal material by stamping. On the wide longitudinal side 7 of the push strip 4, leaf springs 5 are punched axially on one side and notches 8 are punched axially between the leaf springs, while openings 9 are punched successively on the other side,10. on the sliding bar 4, a stamped-out leaf spring 5 is perpendicular to the longitudinal axis 1 in the sliding direction to have the same clear length L_AIs bent over on the longitudinal side 7 of the push strip 4 in a projecting manner. The leaf spring 5 is designed with an additional web 14 depending on the production. The leaf springs 5 are arranged axially one after the other at a predetermined axial distance L, wherein the distance is smaller than the length L_A. This makes it possible to significantly shorten the axial installation length of the actuating unit 2. In order to avoid material overlapping in the axial direction when the leaf springs 5 are stamped out, they are stamped out on the push plate 4 with ends facing away from one another in the axial direction and are bent parallel to one another in opposite bending directions, projecting in the same direction on the push plate 4. In order to be able to maintain the leaf springs 5 on the pusher plate 4 at the same length L in the bent state with a predetermined short axial distance L_AOne of the leaf springs 5 is stamped on the sliding strip 4 with an additional length Δ L. In order to achieve a predetermined spacing length L in the bent state_AThe additional length Δ L of the leaf spring 5 needs to be compensated again in the bending process by additional bending of the additional webs 14. The additional length Δ L is indicated by a curved double arrow at the additional tab 14.

The curved leaf spring 5 is oriented with the wide longitudinal side 13 in the sliding direction of the sliding bar 4 and forms at the free end at least one flat axial contact surface 15 for switching the individual valve train components. In order to increase the contact surface 15, the wide longitudinal sides 13 are widened at the free ends.

In a particularly advantageous manner, the actuating device according to the invention can be used for actuating one or more switchable valve struts in a valve train of an internal combustion engine. The transmission element 5 or the leaf spring is preferably in contact with the contact surface at its free end with a switching element integrated into the respective valve plunger. By displacing the pusher element 4, an axial adjusting movement can be transmitted via the transmission element 5 for switching the respective valve rod. The one or more valve struts can be driven by one or more camshafts of the internal combustion engine by means of a cam stroke movement. This cam path movement can be transmitted at the rod end region of the respective valve slide for actuating at least one gas exchange valve of the internal combustion engine. Preferably, the actuating unit is arranged with the pusher element 4 parallel to the cam shaft. It is also conceivable for the actuating device to have a plurality of actuating units, each of which is formed by a pusher element 4 and one or more transmission elements 5. Switchable valve struts are known in various embodiments. Basically, these valve struts consist of two levers which are mounted in line with one another, wherein preferably one of the levers, the so-called primary lever, is in constant contact with at least one gas exchange valve of the internal combustion engine, while the other lever, the so-called secondary lever, is mounted on the primary lever in a pivotally movable manner. The secondary lever may be turned on or off as needed, for example, when a large valve stroke is required. As a result, a stroke change or a stroke switch-off or a cylinder switch-off can be realized. In the off mode, the secondary lever generally executes an idle stroke as a so-called Lost Motion (Lost-Motion-beegusng).

List of reference numerals

1 longitudinal axis

2 operating unit

3 operating module

4 pusher element, pusher strip

5 Transmission element, leaf spring

6 longitudinal side or material thickness side

7 longitudinal side

8 notch

9 opening

10 opening

11 axle

12 casing

13 longitudinal side

14 attachment tab

15 contact surface

Thickness of S material

s thickness of material

L_ALength of pitch

L pitch

Δ L additional length.