Rocker arm assembly for a valve train of an internal combustion engine

Abstract

Rocker arm arrangement for a valve train of an internal combustion engine, comprising a first switchable rocker arm (1) and a second switchable rocker arm (2), each pivotably arranged on a rocker arm shaft (3) with an axially outer lever (4, 5) and with a lever (6, 7) axially inner next to the rocker arm shaft (3), wherein the levers (4, 5, 6, 7) are pivotably mounted relative to each other on the rocker arm shaft (3), and for switching the first rocker arm (1) the first axially outer lever (4) can be coupled to the first axially inner lever (6) by means of first coupling means (8), and for switching the second rocker arm (2) the second axially outer lever (5) can be coupled to the second axially inner lever (7) by means of second coupling means (9), each for transmitting a stroke movement for valve actuation, characterized in that for actuating the respective coupling means (8, 9) an actuator (10) is assigned to each of these.11) is arranged on the axially outer longitudinal sides (4a, 5a) of the axially outer levers (4, 5) facing away from each other, and the actuators (10, 11) are each integrated into a common support (17) connected to the common rocker arm axis (3) and are arranged at a radial distance from the rocker arm axis (3), wherein the first axially inner lever (6) is in valve contact with at least one inlet gas exchange valve of the internal combustion engine and the second axially inner lever (7) is in valve contact with at least one exhaust gas exchange valve, so that at least one inlet gas exchange valve and at least one exhaust gas exchange valve for a cylinder of the internal combustion engine can be controlled independently of each other by the first switchable rocker arm (1) and by the second switchable rocker arm (2).

Description

The invention relates to a rocker arm arrangement for a valve train of an internal combustion engine according to the type defined in more detail in the preamble of claim 1. From DE 10 2017 129 720 A1, a switchable rocker arm arrangement is known with at least one rocker arm which is mounted on a machine-fixed rocker arm axis and has a cam arm connected to a camshaft and a valve arm connected to at least one gas exchange valve of a reciprocating internal combustion engine. US 2004 / 0255887 A1 discloses a valve train for an internal combustion engine with switching mechanisms for switching the actuation of the valves of the internal combustion engine by connecting follower rocker arms with actuating rocker arms. The invention is therefore based on the objective of proposing a rocker arm arrangement of the aforementioned type, which enables a simple and cost-effective improved variable valve control. The problem is solved by the features of claim 1. Further advantageous embodiments are described in the respective dependent claims, the description, and the drawings. A rocker arm arrangement for the valve train of an internal combustion engine is proposed, comprising a first switchable rocker arm and a second switchable rocker arm. These rocker arms are each pivotably mounted on a rocker arm shaft, with one arm located axially outside and the other axially inside the rocker arm shaft. The rocker arms are pivotally mounted relative to each other on the rocker arm shaft. To switch the first rocker arm, the first axially outside lever can be coupled to the first axially inside lever by means of a first coupling device to transmit a stroke movement for valve actuation. To switch the second rocker arm, the second axially outside lever can be coupled to the second axially inside lever by means of a second coupling device to transmit a stroke movement for valve actuation.For actuating each coupling element, an associated actuator is arranged on the axially outer longitudinal sides of the axially outer levers, facing away from each other. Since an actuator is arranged on the axially outer sides of the axially outer levers, facing away from each other, the installation space between the rocker arms, or between the axially inner levers associated with them, can be kept clear, particularly due to installation constraints or design considerations. The actuators are integrated into a common support connected to the common rocker arm axis and arranged at a radial distance from the rocker arm axis. Furthermore, since each coupling element has an associated actuator for switching, each rocker arm can be individually switched by its respective actuator.This allows the actuators to be made smaller and manufactured in larger numbers at lower production costs. Furthermore, the first axially internal lever is in contact with at least one intake gas exchange valve of the internal combustion engine, and the second axially internal lever is in contact with at least one exhaust gas exchange valve. In a further advantageous embodiment of the invention, the axially outward-positioned levers, acting as levers on the actuating side, are each pivotally driven by a stroke movement from a camshaft. This allows the drive-side stroke movement to be taken as far axially outward as possible. In this way, the cams can be arranged close to the bearing points of the camshaft, thereby reducing the load on the camshaft, particularly from bending. According to the invention, the first axially internal lever is in valve contact with at least one inlet gas exchange valve of the internal combustion engine as the first valve-side lever, and the second axially internal valve-side lever is in valve contact with at least one exhaust gas exchange valve as the second valve-side lever. In this way, at least one inlet gas exchange valve and at least one exhaust gas exchange valve for one cylinder of the internal combustion engine can be controlled independently of each other by means of the first switchable rocker arm. It is also advantageous if the outer actuating levers are pivotably mounted in a central area on the rocker arm axis, situated between an actuating lever end for the pivoting drive and a coupling lever end for coupling with the respective inner lever. In this way, the actuating levers can each be implemented as double-sided levers, ideally symmetrical to the rocker arm axis. This reduces the so-called Steiner component of the moment of inertia during operation and lowers the Hertzian contact stresses on the drive side when a cam stroke movement is taken from a camshaft, particularly with a cam roller. Furthermore, this allows the coupling elements and associated actuators to be arranged on the valve side of the rocker arm axis. Individual actuation of the rocker arms is easily possible if a first actuator is provided for switching first coupling means, by which a first axially outer lever and a first axially inner lever pivotably arranged relative to it can be coupled. A second actuator is provided for switching second coupling means, by which a second axially outer lever and a second axially inner lever pivotably arranged relative to it can be coupled by second coupling means. A further advantage can be achieved if each coupling element has an actuating piston that is movable in an axial through-bore on the respective axially outer actuating lever. This piston is in direct contact with a coupling piston located in an axial bore on the respective axially inner lever, allowing it to be moved for switching. The latter can be moved into the through-bore of the outer lever to couple with it. The coupling elements can thus be arranged parallel to the rocker arm axis and transverse to the longitudinal axis of the rocker arms, and moved for switching. In this way, the rocker arms can be switched by a space-saving transverse locking mechanism, which also allows the coupling elements to be arranged close to the rocker arm axis. It is particularly advantageous if the coupling means are pre-tensioned by springs to couple the respective outer lever with the respective inner lever into the respective coupled state. This ensures that, in the unactuated state of the actuators, the respective rocker arms remain locked, and that a valve stroke movement can be transmitted to the respective gas exchange valves. In a further advantageous embodiment of the invention, the actuating pistons are each expanded at at least one axial end face in the outer diameter such that, during a relative pivoting of the respective outer lever with respect to the respective actuator and / or with respect to the respective coupling piston, at least partial axial overlap between the respective actuating piston and the respective actuator and / or with respect to the respective coupling piston is ensured for switching. In this way, the actuating pistons and the respective coupling pistons can be permanently controlled for switching by the respective actuator. It is also possible, for example, to arrange the actuating pistons with an actuator-side end face protruding from the through-bore and to expand them beyond the bore diameter.The actuating pistons can be in permanent contact on the actuator side and the coupling piston side during overlapping, or they can be spaced apart by a small air gap. The design can be further simplified if the actuators are implemented as electric solenoids, each featuring a linearly displaceable armature through which the respective actuating piston can be moved for switching in direct axial contact. These solenoids can also be manufactured cost-effectively in large quantities. According to the invention, the actuators are each integrated into a carrier connected to the rocker arm axis and arranged radially spaced from the rocker arm axis. This allows the actuators to be arranged on the carrier at any desired individual radial distance from the rocker arm axis in a particularly simple manner. This enables the actuators and the coupling means to be switched close to the rocker arm axis, so that the relative movement of coupling means integrated, for example, into the valve-side lever or an actuating-side lever, is minimal during operation. Permanent contact for switching between the actuator and the coupling means can thus be easily established. Furthermore, the rocker arm assembly with the actuators, the rocker arm axis, and the rocker arms can be easily attached to the cylinder head of the internal combustion engine via the carrier, particularly by means of a bolted connection, as a pre-assembled unit. Return spring elements can be provided, each with a coil-shaped base body arranged coaxially on the axial outer sides of the outer levers on the rocker arm shaft. One spring leg is clamped to the rocker arm shaft in the pivoting direction. Preferably, the other spring leg is clamped to the respective axially outer actuating lever in the pivoting direction. The return spring elements are thus guided on the outer diameter of the rocker arm shaft with the inner diameter of the base body. They are preferably designed as torsion springs, specifically as torsion springs, and serve to return the respective levers in a decoupled state from a pivoted position to an unpivoted home position. This avoids the need to arrange the return spring elements axially between the rocker arms. The first and second rocker arms can be switched and actuated independently of each other. For example, it is possible to actuate at least one intake gas exchange valve of the internal combustion engine using the first rocker arm and at least one exhaust gas exchange valve using the second rocker arm. Conversely, it is also conceivable to actuate at least one exhaust gas exchange valve using the first rocker arm and at least one intake gas exchange valve using the second rocker arm. Integrating the actuators into a common carrier connected to the shared rocker arm shaft, on which the switchable rocker arms with their valve-side and actuator-side levers are mounted, allows the rocker arm assembly to be designed as a pre-assembled unit that can be easily attached to the cylinder head of the internal combustion engine via the carrier. A screw connection can be provided for attaching the rocker arm shaft to the carrier and for attaching the carrier to the cylinder head. The switchable rocker arm assembly can thus be individually mounted directly to the cylinder head for each cylinder. It is also possible to arrange multiple rocker arms on a common rocker arm shaft for all cylinders. Accordingly, it can then be selected whether all or only some cylinders are equipped with the switchable rocker arm unit.For example, to deactivate cylinders, only half of the internal combustion engine's cylinders can be equipped with the rocker arm arrangement. However, it is also conceivable to equip all cylinders accordingly if overrun fuel cut-off or so-called coasting operation of the engine is to be implemented. The invention is explained in more detail with reference to the drawings. They show: Fig. 1 a rocker arm arrangement according to the invention in a first operating state, Fig. 2 the rocker arm arrangement according to the invention in a second operating state, Fig. 3 a sectioned, enlarged detail from Fig. 2 in a first switching state, Fig. 4 the enlarged detail from Fig. 2 in a second switching state, Fig. 5 an enlarged detail from Fig. 1 in the second switching state. The rocker arm arrangement according to the invention for a valve train of an internal combustion engine, shown in Figures 1 and 2, comprises a first switchable rocker arm 1 and a second switchable rocker arm 2, which are arranged on a common rocker arm shaft 3 that is fixed in a specific location or on the machine. The first rocker arm 1 is pivotably arranged on the rocker arm shaft 3 by means of a first lever 4, which is arranged axially outside on the rocker arm shaft 3, and a first lever 6, which is arranged axially inside next to the first lever 4 on the rocker arm shaft 3. The second rocker arm 2 is pivotably arranged on the rocker arm shaft 3 by means of a second lever 5, which is arranged axially outside on the rocker arm shaft 3, and a second lever 7, which is arranged axially inside next to the second lever 5 on the rocker arm shaft 3.Here, the axially inner levers 6, 7 are arranged with their axially inner lever faces 6a, 7a facing each other, while the axially outer levers 4, 5 are positioned on the respective axially outer lever faces 6b, 7b of the axially inner levers 6, 7 that face away from each other. The valve-side and actuator-side levers 4, 5, 6, 7 are each pivotably arranged relative to each other on the rocker arm axis 3. To actuate the first rocker arm 1, the first axially outer lever 4 can be coupled to the first axially inner lever 6 by means of first coupling means 8. To actuate the second rocker arm 2, the second axially outer lever 5 can be coupled to the second axially inner lever 7 by means of second coupling means 9. An actuator 10, 11 is arranged on each of the axially outer lever faces 4a, 5a of the axially outer levers 4, 5, facing away from each other. A first actuator 10 is arranged on the axially outer lever face 4a of the first axially outer lever 4 to actuate the first coupling means 8. A second actuator 10 is positioned on the axially outer lever face 5a of the second axially outer lever 5 to actuate the second coupling means 8. In this way, the coupling means 8, 9 can each be actuated by a separate, associated electrical actuator 10, 11. The axially outer levers 4, 5 are pivotally actuated as actuating-side levers. For this purpose, each lever is in contact at one end with a cam roller 12, 13, which in turn contacts an associated cam 14, 15 of a camshaft 27 of the internal combustion engine to detect a cam stroke movement. The axially inner levers 6, 7 serve as valve-side levers, each transmitting the cam stroke movement detected by the axially outer actuating-side and cam-side levers 4, 5 as a valve stroke movement to at least one gas exchange valve (not shown) of the internal combustion engine. For this purpose, the axially inner levers 6, 7 are in contact at one valve-side lever end with one or more gas exchange valves (not shown) of a cylinder of the internal combustion engine. The first switchable rocker arm 1 has a first axially external actuating-side lever 4 and a first axially internal valve-side lever 6, the latter of which actuates two intake gas exchange valves (not shown) when in valve contact. The second switchable rocker arm 2 comprises a second axially external actuating-side lever 5 and a second axially internal valve-side lever 7, by which two exhaust gas exchange valves (not shown) can be actuated when in valve contact. Two gas exchange valves, i.e., four gas exchange valves per cylinder, can be actuated simultaneously via a forked valve contact (not shown), a so-called valve bridge, at the valve-side lever end region of the respective axially internal valve-side levers 6 and 7. Alternatively, only one gas exchange valve, i.e., two gas exchange valves per cylinder, can be actuated at a time, in which case a valve bridge is not required.The rocker arm arrangement shown in Figs. 1 and 2, with the two switchable rocker arms 1, 2, serves for cylinder deactivation on an engine (not shown) for a truck, which is depicted with a single overhead camshaft 27 driving the rocker arms 1, 2. The rocker arm arrangement can also be used for an engine with a single overhead camshaft. With appropriate modifications, it is also conceivable to use it for an engine with two overhead camshafts. The outer actuating levers 4, 5 are each mounted in a central area on the rocker arm axis 3, located between their coupling-side ends and their camshaft-side ends. They are thus configured as a two-sided lever, with their ends pivotable around the rocker arm axis 3. In Fig. 1, the rocker arm arrangement is shown in a first operating state during the base circle phase of the cams 14, 15, while in Fig. 2, in a second operating state, an intake cam 14 is in the cam lift phase and an exhaust cam 15 is in the base circle phase. During the cam lift phase, the respective axially outer actuating-side lever 4, 5 is actuated by the tapping of a cam lift, while it is unactuated during the base circle phase. Figures 3, 4 to 5 each show an enlarged section of the first rocker arm 1 for actuating the inlet gas exchange valves in the area of ​​the associated first coupling means 8 and an associated first actuator 10 in various switching states. The first coupling means 8 have an actuating piston 8a and a coupling piston 8b. The actuating piston 8a is slidably arranged in an axial through-bore 4b at the coupling-side end of the respective first axially outer actuating-side lever 4 for switching. The coupling piston 8b is slidably received in an axial bore 6c on the first axially inner valve-side lever 6. The bore 6c is also designed as an axial through-bore. The actuating piston 8a is slidably moved by the first actuator 10 at an actuating-side end face 8c for switching. It is in contact with the coupling piston 8b at the other end face 8d.The latter is pre-tensioned against the actuating piston 8a by spring means 16, which is arranged coaxially in the bore 6c as a helical compression spring. The movement of the actuating piston 8a is limited on the actuating side by a bushing 24 pressed into the through-bore 4b at the actuating end and by a stop 24a formed axially on its end face. Similarly, the movement of the coupling piston 8b is limited in both directions of displacement by two bushings 25, 26 pressed into the respective ends of the bore 6c and by stops 25a and 26a formed axially on their end faces. The second coupling means 9 of the second rocker arm 2 are constructed analogously to those of the first rocker arm 1 and are arranged in a mirror image of them in the axial direction (Fig. 1 and Fig. 2). The coupling means 8, 9 are each integrated in this way into the respective valve-side levers 6, 7 and into the respective actuation-side levers 4, 5. A common carrier 17 is provided to accommodate the actuators 10, 11 (Figs. 1 and 2). The actuators 10, 11 are formed by electric lifting magnets, each of which is received in a socket 17a, 17b of the carrier 17 (Figs. 3, 4 to 5). The actuators 10, 11 are arranged coaxially with respect to the respective coupling means 8, 9 (Figs. 1 and 2). They each have an armature 10a that is electromagnetically displaceable axially relative to the actuating piston 8a (Figs. 3, 4 to 5). The actuators 10, 11 with the anchors 10a and the coupling means 8, 9 in the bores 6c and the through bores 4b are each arranged parallel to the rocker arm axis 3 and transversely to the longitudinal axis of the rocker arms 1, 2, or are displaceable for switching. In this way, the rocker arms 1, 2 can be switched by a space-saving so-called transverse locking mechanism. In a first switching state according to Fig. 3, the actuator 10 is in the unactuated, i.e., de-energized, state. The armature 10a is pushed back into the bushing 17a by integrated return spring means 10b (Fig. 3). During the base circle phase (Fig. 1), when the actuating-side lever 4 and the valve-side lever 6 are in their neutral, unpivoted home position, the bore 6c on the valve-side lever 6 and the through-bore 4b of the actuating-side lever 4 are axially aligned. The spring force of the spring means 16 moves the coupling piston 8b out of the through-bore 4b, across the parting line between the valve-side lever 6 and the actuating-side lever 4, and into the through-bore 4b (Fig. 3), thus coupling the valve-side lever 6 to the actuating-side lever 4. The coupling pistons 8b and the actuating pistons 8a remain in contact at their facing end faces 8d.The separating plane between the valve-side lever 6 and the actuating-side lever 4 is formed by a small axial air gap. In the third operating state according to Fig. 3, during the cam stroke phase of the first rocker arm 1 according to Fig. 2, the cam stroke movement taken from the actuating-side lever 4 at the first cam is transmitted to the valve-side lever 6, thereby opening the inlet gas exchange valves. Similarly, the second actuating-side lever 5 can be coupled to the second valve-side lever 7 by means of the second coupling means 9 and the second actuator 11, and the second rocker arm 2 can be switched, thereby actuating the exhaust gas exchange valves to open. By energizing the lifting magnets, the actuator 10 is actuated in a fourth operating state as shown in Figs. 4 and 5. The armature 10a moves out of the bushing 17a against the spring force of the return spring means 10b and comes into contact with the actuating piston 8a. This biases the latter against the coupling piston 8b. During the basic rotation phase (Fig. 1), the actuating piston 8a moves the coupling piston 8b from the through-bore 4b into the dividing plane between the valve-side lever 6 and the actuating-side lever 4 (Figs. 3 and 4), thereby decoupling the levers 4 and 6. The actuating-side lever 4 is in its free stroke, and the first rocker arm 1 is deactivated. As a result, in the fourth operating state according to Fig. 4, no cam stroke movement is transmitted to the valve-side lever 6 in the cam stroke phase of the first rocker arm 1 shown in Fig. 2, thereby closing the inlet gas exchange valves.Similarly, the second coupling means 9 and the second actuator 11 can couple the second actuation-side lever 5 with the second valve-side lever 7, deactivating the second rocker arm 2 and closing the exhaust gas exchange valves. In this way, cylinder deactivation is achieved by the rocker arm arrangement with the first and second rocker arms 1, 2 deactivated. The actuating piston 8a is mushroom-shaped at its axial end faces 8c, 8d, such that when the actuating-side lever 4 pivots relative to the armature 10a and the coupling piston 8b, at least partial axial end-face overlap is ensured (Figs. 4 and 5). Its actuator-side end 8c is positioned outside the through-bore 4b and is expanded beyond the bore diameter. The actuating piston of the second coupling means 9 (not shown) can be expanded in the same way at its axial end faces. To return the axially outward actuating levers 4, 5 from a pivoted position to an unpivoted home position, return spring elements 18, 19 are provided (Figs. 1 and 2). These are arranged coaxially on the rocker arm shaft 3 with a coil-shaped base body 18a, 19a on the axial outer sides of the axially outward actuating levers 4, 5 (Figs. 1, 2, 3, 4 to 5). The return spring elements 18, 19 are guided on the outer diameter of the rocker arm shaft 3 with the inner diameter of the base body 18a, 19a. A first spring leg 18b, 19b engages in a radially extending groove 20, 21 at the axially end face of the rocker arm shaft 3, clamped in the pivoting direction. A second spring leg 18c, 19c bridges the respective outer lever 4 or 5 at its connection to the gas exchange valves orupper side facing away from the cylinder head in the axial direction and is clamped in the pivoting direction on the axial inside of the respective outer lever 4 or 5 (Fig. 3, Fig. 4 to Fig. 5). The carrier 17 has a central, elongated rectangular base plate 17c, which runs parallel to the rocker arm axis 3 below the underside of the axially inner valve-side levers 6, 7 and the underside of the axially outer actuating-side levers 4, 5, which face the gas exchange valves or the cylinder head of the internal combustion engine (not shown) (Figs. 1 and 2). The base plate 17c is provided at each of its axial ends with an arm 17d projecting perpendicularly away from the cylinder head, which forms bushings 17a, 17b at its free end. The bushings are axially opposite the outer longitudinal sides 4a, 5a of the axially outer actuating-side levers 4, 5 and accommodate the actuators 10, 11. On the upper surface of the base plate 17c, facing away from the cylinder head, a projecting support section 17f is formed in an area located axially between the axially internal valve-side levers 6, 7. This section is aligned towards the rocker arm axis 3. The rocker arm axis 3 is attached to this support section via a first screw connection 22. A second screw connection 23 on the base plate 17c allows the support 17 to be attached to the cylinder head (not shown). In this way, the support 17, together with the rocker arm axis 3, the rocker arms 1, 2 arranged on it, the return spring elements 18, 19, and the actuators 8, 9 mounted on the support 17, can be attached to the cylinder head as a pre-assembled unit. The rocker arms 1 and 2 can each be actuated individually by actuators 10 and 11, respectively. The solenoids of actuators 10 and 11 are controlled by electronic control units (not shown). For this purpose, a central contact, specifically a central connector, is integrated into the rocker arm assembly. A connection to the engine control unit (not shown) is located outside the cylinder head of the internal combustion engine. The solenoids can be activated by a switching command from the engine control unit, a so-called CAN signal. The integrated electronics calculate the exact energizing time of the solenoids. Furthermore, the integrated electronics also determine which of the individual solenoids is activated. Reference symbol list 1 Rocker arm 2 Rocker arm 3 Rocker arm shaft 4 Lever 4a Lever side 4b Through hole 5 Lever 6 Lever 6a Lever side 6b Lever side 6c Bore 7 Lever 7a Lever side 7b Lever side 8 Coupling element 8a Actuating piston 8b Coupling piston 8c End 8d End 9 Coupling element 10 Actuator 10a Armature 10b Return spring element 11 Actuator 12 Cam roller 13 Cam roller 14 Cam 15 Cam 16 Spring element 17 Carrier 17a Bushing 17b Bushing 17c Base plate 17d Arm 17f Support section 18 Return spring element 18a Base body 18b Spring leg 18c Spring leg 19 Return spring element 19a Base body 19b Spring leg 19c Spring leg 20 Groove 21 Groove 22 Screw connection 23 Screw connection 24 Bushing 24a Stop 25 Bushing 25a Stop 26 Bushing 26a Stop 27 Camshaft

Claims

Rocker arm arrangement for a valve train of an internal combustion engine, comprising a first switchable rocker arm (1) and a second switchable rocker arm (2), each pivotably arranged on a rocker arm shaft (3) with an axially outer lever (4, 5) and with a lever (6, 7) axially inner next to the latter on the rocker arm shaft (3), wherein the levers (4, 5, 6, 7) are pivotably mounted relative to each other on the rocker arm shaft (3), and for switching the first rocker arm (1) the first axially outer lever (4) is coupled to the first axially inner lever (6) by means of first coupling means (8), and for switching the second rocker arm (2) the second axially outer lever (5) is coupled to the second axially inner lever (7) by means of second coupling means (9), each for transmitting a stroke movement for valve actuation, characterized in that for actuating the respective coupling means (8, 9) an actuator (10) is assigned to each of these.11) is arranged on the axially outer longitudinal sides (4a, 5a) of the axially outer levers (4, 5) facing away from each other, and the actuators (10, 11) are each integrated into a common support (17) connected to the common rocker arm axis (3) and are arranged at a radial distance from the rocker arm axis (3), wherein the first axially inner lever (6) is in valve contact with at least one inlet gas exchange valve of the internal combustion engine and the second axially inner lever (7) is in valve contact with at least one exhaust gas exchange valve, so that at least one inlet gas exchange valve and at least one exhaust gas exchange valve for a cylinder of the internal combustion engine can be controlled independently of each other by the first switchable rocker arm (1) and by the second switchable rocker arm (2). Rocker arm arrangement according to claim 1, characterized in that the axially outer levers (4, 5) can each be pivotally driven by a camshaft (27) of the internal combustion engine with a lifting movement. Rocker arm arrangement according to one of claims 1 or 2, characterized in that the axially outer levers (4, 5) are each pivotably driven with an actuating-side lever end region and are coupled with a coupling-side lever end region to the respective axially inner lever (6, 7), wherein the axially outer levers (4, 5) are each pivotably mounted in a central area located between the actuating-side lever end region and the coupling-side lever end region on the rocker arm axis (3). A rocker arm arrangement according to one of claims 1 to 3, characterized in that the coupling means (8, 9) each have an actuating piston (8a) which is displaceable in an axial through-bore (4b) on the respective axially outer lever (4, 5), by which a coupling piston (8b) arranged in an axial bore (6c) on the respective axially inner lever (6, 7) is displaceable for switching in direct actuating contact, wherein the latter is displaceable into the through-bore (4b) of the respective outer lever (4, 5) for coupling. Rocker arm arrangement according to claim 4, characterized in that the actuating pistons (8a) are each expanded at at least one axial end face (8c) in the outer diameter such that, when the respective outer lever (4, 5) is pivoted relative to the respective actuator (10, 11) and / or relative to the respective coupling piston (8b), at least partial axial overlap is ensured between the respective actuating piston (8a) and the respective actuator (10, 11) and / or relative to the respective coupling piston (8b) for switching. Toggle lever arrangement according to one of claims 1 to 5, characterized in that the actuators (10, 11) are designed as electric lifting magnets, each having a linearly displaceable armature (10a) through which the respective associated coupling means (8, 9) can be displaced for switching in direct axial actuating contact. Rocker arm arrangement according to one of claims 1 to 6, characterized in that return spring means (18, 19) are arranged coaxially on the rocker arm axis (3) at the axial outer sides of the outer levers (4, 5) with a coil-shaped base body (19a, 19b) encompassing these on the rocker arm axis (3) and are clamped in the pivoting direction with one spring leg (18a) on the rocker arm axis (3) and with the other spring leg (18b) on the respective axially outer lever (4, 5).

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