Rocker device for a valve train of an internal combustion engine

Abstract

The invention relates to a rocker device for a valve train of an internal combustion engine, having at least one rocker (1) which is pivotably arranged on a rocker shaft (3) with one lever (1a) for actuating the valve side of at least one gas exchange valve (4, 5) of the internal combustion engine and with two levers (1b, 1c) for the pivotably drivable actuating side, wherein the levers (1a, 1b, 1c) are pivotably supported on the rocker shaft (3) relative to one another and, in order to switch the rocker (1), the first lever (1b) of the actuating side can be coupled to the lever (1a) of the valve side by means of a first coupling mechanism (9) in order to transmit a first lift movement for valve actuation, and the second lever (1c) of the actuating side can be coupled to the lever (1a) of the valve side by means of a second coupling mechanism (10) in order to transmit a second lift movement for valve actuation.

Description

Technical Field

[0001] This invention relates to a rocker arm device for the valve mechanism of an internal combustion engine. Background Technology

[0002] A switchable rocker device with a rocker arm is known from DE 10 2017 129 720 A1. The rocker arm is supported on a rocker shaft fixed to a machine and has a cam arm connected to a camshaft and a valve arm connected to at least one scavenging valve of a reciprocating piston internal combustion engine.

[0003] The valve mechanism system for an engine known from US 2006 / 0236968 A1 is designed with a low-lift rocker arm, a high-lift rocker arm, and a connecting rocker arm, wherein these rocker arms can be connected by a low-lift locking mechanism and a high-lift locking mechanism.

[0004] US 2016 / 0230679 discloses a variable valve mechanism system with three rocker arms that can be connected via a switching mechanism.

[0005] The variable valve mechanism disclosed in JP 2013-142328 A has a main rocker arm and two cam follower rocker arms, which can be interconnected by a changeover pin. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to provide the aforementioned rocker arm device, which enables variable valve control with a simple structure and improved performance during operation.

[0007] A rocker arm device for a valve mechanism of an internal combustion engine is proposed, comprising at least one rocker arm. The rocker arm is pivotally mounted on a rocker arm shaft with a lever on the valve side for operating at least one scavenging valve of the internal combustion engine and two levers on the operating side for pivotally driven movement, wherein the levers are pivotally supported on the rocker arm shaft relative to each other. To switch the rocker arm, the first lever on the operating side can be connected to the lever on the valve side via a first coupling mechanism to transmit a first lift movement for valve operation, and the second lever on the operating side can be connected to the lever on the valve side via a second coupling mechanism to transmit a second lift movement for valve operation. In this way, the levers on the valve side can be selectively switched separately by the levers on the operating side. A simple multi-stage variable operation, particularly a combination of valve lift cut-off and valve lift conversion, can be achieved by means of at least one switchable rocker arm. Here, valve lift can be completely cut off, or an additional valve lift relative to full valve lift can be engaged, or the latter can be deactivated. Another advantage is that the valve lift height of the additional valve lift can be adjusted to be less than that of the full valve lift, and in particular, it can be directly adjusted to be lower than the valve lift height. This enables the so-called Miller-Hub.

[0008] In a particularly advantageous manner, four distinct and independent lift profiles can be transmitted via a rocker arm. The valve-side lever can be decoupled from the two control-side levers, thereby achieving valve lift cutoff in the base circle profile. The valve-side lever can be coupled to the first control-side lever, while the valve-side lever can be decoupled from the second control-side lever. Thus, in the second lift profile, only the full valve lift, for example, picked up from the master camshaft, can be transmitted. The valve-side lever can be coupled to both control-side levers simultaneously, thereby transmitting a combination of full valve lift and additional valve lift in the third lift profile. This is particularly advantageous in the so-called internal exhaust gas recirculation of internal combustion engines. In the fourth lift profile, the valve-side lever can be coupled to the second control-side lever, while the valve-side lever can be decoupled from the first control-side lever. Thus, only one additional valve lift, for example, picked up from the secondary camshaft, can be transmitted. For example, this is the case for the Miller lift mentioned above at the intake valve side, or for engine braking, and / or for so-called engine thermal management implemented at the exhaust valve side to reduce the thermal load and wear on components.

[0009] In another advantageous embodiment of the invention, in addition to the switchable first rocker arm, a switchable second rocker arm is also provided. The second rocker arm is pivotally mounted on a rocker shaft as a lever on the valve side for operating at least one scavenging valve of the internal combustion engine and as a third lever on the operating side for pivotally actuating movement, wherein the levers are pivotally supported on the rocker shaft relative to each other. To switch the second rocker arm, the third lever on the operating side can be coupled to the second lever on the valve side via a third coupling mechanism for transmitting a third lift movement for valve actuation. In this way, the second rocker arm is switched independently of the first rocker arm, and vice versa.

[0010] In this additional advantageous manner, at least one exhaust valve for a cylinder of the internal combustion engine can be independently operated via a switchable first rocker arm, and at least one intake valve can be independently operated via a switchable second rocker arm. This can be easily achieved in such a way that a first lever on the valve side makes valve contact with at least one exhaust valve of the internal combustion engine, and a second lever on the valve side makes valve contact with at least one intake valve.

[0011] In another particularly advantageous embodiment of the invention, the first lever on the control side and the third lever on the control side respectively contact the first cam of the camshaft of the internal combustion engine to pick up the full valve lift for valve control. Thus, the transmission, cut-off, or combined cylinder deactivation of the full valve lift can be achieved independently on the first rocker and the second rocker. Since the second lever on the control side for picking up additional valve lift contacts the second cam of the camshaft, the additional valve lift can be transmitted on the first rocker only when the camshaft is rotating, either without full valve lift or along with full valve lift. Furthermore, this arrangement enables alternating or flipping cylinder deactivation and simultaneously enables graded or selectively independent engine braking for each cylinder. The levers on the control side allow direct pickup of lift movement from the corresponding cam of the camshaft, thereby eliminating the need for additional transmission mechanisms. The cam rollers minimize frictional losses during pickup.

[0012] The design can be further simplified by equipping each coupling mechanism with an actuator for switching, and allowing each rocker arm to be switched individually by a separate actuator. This allows for smaller actuators and enables mass production at a lower manufacturing cost.

[0013] Advantageously, the actuator is designed as an electric solenoid, each with a linearly movable armature. The corresponding coupling mechanism moves through this armature in direct adjusting contact for switching. This eliminates the need for additional components to transmit the adjusting motion. The actuator stroke is reduced, and the switching time is shortened. Furthermore, direct, individual operation of the corresponding rocker arm improves switching performance while simultaneously reducing variations in switching time. The effects of component tolerances and manufacturing costs can be minimized.

[0014] The actuator can be at least partially integrated into a bracket connected to the rocker shaft and positioned radially relative to the rocker shaft. On this bracket, the actuator can thus be positioned individually at any separate radial distance from the rocker shaft in a particularly simple manner. This allows for switching of the actuator arrangement and coupling mechanism near the rocker shaft, resulting in minimal relative movement during operation of the coupling mechanism, such as that integrated into a lever on the valve side or a lever on the operating side. Therefore, a permanent contact for switching can be easily established between the actuator and the coupling mechanism. Furthermore, the rocker assembly, comprising the actuator, rocker shaft, and rocker, can be easily fixed to the cylinder head of an internal combustion engine as a pre-assembleable structural unit via the bracket, particularly via threaded connections.

[0015] In another advantageous embodiment of the invention, the coupling mechanism is integrated into the rocker arm and movably disposed in axial holes on the valve-side lever and the respective associated levers on the control side for switching. In this way, an axial connection can be achieved between the respective valve-side and control-side levers and their longitudinal axis, thus enabling a so-called lateral locking of the switchable rocker arm. Lateral locking allows for a space-saving arrangement of the coupling mechanism near the rocker arm axis.

[0016] Here, the first coupling mechanism and the third coupling mechanism each have an operating piston movable in an axially through-hole on a corresponding first lever and third lever on the valve side. Through this operating piston, a connecting piston disposed in the axial hole on the first lever and third lever on the operating side can be moved accordingly in direct adjusting contact for switching. Here, the connecting piston can be moved into the through-hole of the lever in order to couple with the corresponding first lever and third lever on the valve side.

[0017] Furthermore, it is advantageous that the coupling mechanism, movably integrated into the lever on the valve side or the lever on the operating side for switching, and at least one actuator associated with the coupling mechanism for switching, ensure at least partial overlap in the direction of movement between the coupling mechanism and the actuator during relative pivoting of the respective lever on the valve side or the corresponding lever on the operating side relative to the respective actuator, so as to facilitate switching. In this way, the coupling mechanism can always be operated by the actuator for switching. During operation, the coupling mechanism can always be in contact with the actuator side or spaced apart by a small air gap.

[0018] Alternatively, it is also possible to configure a coupling mechanism movably integrated into the lever on the control side for switching, and at least one actuator integrated into the bracket for operating the coupling mechanism, such that when the lever on the control side or the lever on the valve side pivots relative to the bracket, the coupling mechanism, in the decoupled state, can abut against the bracket in the direction of movement on the actuator side. Therefore, in the decoupled state, the coupling mechanism can permanently abut against the bracket with a sliding pivotal contact. This achieves simple and permanent fixation to prevent the coupling mechanism from detaching from the lever on the control side or the lever on the valve side. The coupling mechanism movably integrated into the lever on the valve side for switching can be fixed in a similar manner in the decoupled state to prevent detachment.

[0019] A return spring mechanism can be provided, which preloads at least one lever on the operating side and at least one corresponding lever on the valve side relative to each other in the pivoting direction to their unpivoted initial positions. Here, axially aligned opposing gaps are provided on the respective levers on the operating side and the valve side, respectively, on their respective axially opposed longitudinal sides. The return spring mechanism is at least partially disposed in these gaps and clamped in the pivoting direction. The return spring mechanism can therefore be integrated into one or two rockers with particularly space-saving structural design.

[0020] In another particularly advantageous embodiment of the invention, a first coupling mechanism and a third coupling mechanism for coupling the first and second levers on the valve side to the first and third levers on the operating side are preloaded in the coupled state by spring mechanisms. Here, a second coupling mechanism for coupling the first lever on the valve side to the second lever on the operating side is preloaded in the decoupled state by spring mechanisms. Therefore, in a simple manner, in the unoperated state of the coupling mechanisms, the first and second levers on the valve side can be held in the coupled state with the first and third levers on the operating side by the first and third coupling mechanisms, while the first lever on the valve side is decoupled from the second lever on the operating side. Thus, for example, the full valve lift can be transmitted via the first and second rockers, while the additional valve lift is deactivated.

[0021] The first and second rocker arms can be switched and operated independently of each other. For example, it is possible to operate at least one exhaust valve of the internal combustion engine via the first rocker arm and at least one intake valve via the second rocker arm. Conversely, it is also conceivable to operate at least one intake valve via the first rocker arm and at least one exhaust valve via the second rocker arm.

[0022] The actuator is integrated into a common bracket connected to a common rocker shaft. A switchable rocker arm with valve-side and control-side rockers is mounted on this bracket. This integration allows the rocker arm assembly to be designed as a pre-assembled structural unit that can be easily fixed to the cylinder head of the internal combustion engine via the bracket. A threaded connection can be provided for fixing the rocker shaft to the bracket and for fixing the bracket to the cylinder head. Therefore, the switchable rocker arm assembly can be directly fixed to the cylinder head individually for each cylinder. Multiple rockers can also be mounted on a common rocker shaft for the entire number of cylinders. Accordingly, it is also possible to select whether only a single cylinder has a switchable rocker arm unit. For example, for cylinder deactivation, only half of the cylinders in the internal combustion engine can be equipped with a rocker arm assembly. It is also conceivable that all cylinders could be equipped accordingly when engine cut-off feed or so-called coasting operation is required. Attached Figure Description

[0023] Other features of the invention will be derived from the following description and accompanying drawings, in which one embodiment of the invention is illustrated in a simplified manner. The drawings are as follows:

[0024] Figures 1 to 3 Perspective views of the rocker device according to the present invention under different operating states are shown respectively. Figure 4 This shows a view of the rocker arm assembly in the first cross-section during the first switching state. Figure 5 This shows a view of the rocker arm assembly in a second cross-section during the first switching state. Figure 6 This shows a view of the rocker arm assembly in the second switching state, cut across the first section plane. Figure 7 This shows a view of the joystick assembly in the second section plane during the third switching state. Figure 8 This shows a view of the rocker assembly cut in the third section. Detailed Implementation

[0025] exist Figures 1 to 3The rocker arm device according to the invention shown has a first rocker arm 1 and a second rocker arm 2, which are mounted on a common rocker arm shaft 3 fixed in a position or fixed to the machine. The first rocker arm 1 consists of a first lever 1a on the valve side for operating the two exhaust valves 4 and 5 of the internal combustion engine, and two levers 1b and 1c on the control side for pivotally driven movement. The second rocker arm 2 includes a second lever 2a on the valve side for operating the two intake valves 6 and 7 of the internal combustion engine, and a third lever 2b on the control side for pivotally driven movement. The valve-side and control-side levers 1a, 1b, 1c, 2a, and 2b are pivotally supported on the rocker arm shaft 3. The pivotal movement of the control-side levers 1b, 1c, and 2b is driven by a camshaft 8 located above.

[0026] To switch the first rocker arm 1, the first lever 1b can be coupled to the first lever 1a on the valve side via the first coupling mechanism 9, and the second lever 1c on the control side can be coupled to the first lever 1a on the valve side via the second coupling mechanism 10. In this way, the first rocker arm is designed as a switchable triple rocker arm. To switch the second rocker arm 2, the second lever 2a on the valve side can be coupled to the third lever 2b on the control side via the third coupling mechanism 11. Here, coupling mechanisms 9, 10, and 11 can be selectively switched by the individual electric actuators 12, 13, and 14 respectively.

[0027] To enable pivotal movement, levers 1b, 1c, and 2b on the control side directly contact the cams 18, 19, and 20 of the camshaft 8 at one end using cam rollers 15, 16, and 17, respectively, to pick up cam lift motion. Levers 1a and 2a on the valve side transmit the cam lift motion picked up by levers 1b, 1c, and 2b on the control side as valve lift motion to the corresponding valves 4, 5 or 6, 7 of the internal combustion engine. For this purpose, levers 1a and 2a on the valve side contact the two exhaust valves 4, 5 or the two intake valves 6, 7 of the internal combustion engine cylinder at their respective lever ends. Through the forked valve contacts 21 and 22, or so-called valve bridges, on the lever ends of the corresponding axially located valve-side levers 1a and 2a, two valves 4, 5 or 6, 7 can be operated simultaneously, meaning four valves per cylinder. Alternatively, it is also possible to operate only one valve per cylinder, meaning two valves per cylinder, where no valve bridge is required. Figure 1 and Figure 2 The rocker assembly shown has two switchable rockers 1 and 2 for variable valve control on an engine for a heavy-duty vehicle (not shown further), which is shown as a camshaft 8 located above the rockers 1 and 2.

[0028] The levers 1a and 2a on the valve side are respectively constructed as levers on both sides, and their rotation points on the rocker shaft 3 are located in the middle region between the lever end region on the valve side with valve contacts 21 and 22 and the lever end region 23 and 24 on the connecting side, so that the lever end region on the valve side and the lever end region 23 and 24 on the connecting side can pivot around the rocker shaft 3. On the lever end region 23 or 24 on the connecting side, the lever 1a or 2a on the valve side can be coupled with the levers 1b, 1c or 2b on the operating side to transmit valve lift movement. Thus, the coupling mechanisms 9, 10, 11 and the associated actuators 12, 13, 14 can be arranged on the camshaft side of the rocker shaft 3 between the rocker shaft 3 and the camshaft 8.

[0029] The levers 1b, 1c, or 2b on the control side are arranged parallel to the levers 1a and 2a on the valve side and are pivotally supported on a common rocker shaft 3 at one end of each support side. The first lever 1b on the control side is located on the longitudinal side of the first lever 1a on the valve side, away from the axially outer side of the second rocker 2, while the second lever 1c on the control side is located on the longitudinal side of the first lever 1a on the valve side, facing the axially inner side of the second rocker 2. The third lever 2b on the control side is arranged on the longitudinal side of the second lever 2a on the valve side, away from the axially outer side of the first rocker 1.

[0030] The levers 1b, 1c, and 2b on the control side respectively utilize cam rollers 15, 16, and 17 to pick up the cam lift motion of the corresponding cams 18, 19, and 20 of the camshaft 8 for valve control. Cam rollers 15, 16, and 17 are respectively mounted on the ends of the levers 1b and 1c on the control side away from the support side. The first lever 1b on the control side utilizes cam roller 15 to pick up the first lift motion of the first cam 18 (which is the primary cam) as the first lift of the valve, while the second lever 1c on the control side utilizes cam roller 16 to pick up the second lift motion of the second cam 19 (which is the secondary cam) as the second lift of the valve, as the second lift of the valve. Through the third lever 2b on the control side, the cam roller 17 can pick up the third lift motion of the third cam 20 of the camshaft 8 as the third lift of the valve. In this way, through the first lever 1a on the valve side, the full valve lift and / or the additional valve lift can be transmitted to the exhaust valves 4 and 5. Through the second lever 2a on the valve side, the full valve lift can be transmitted to the intake valves 6 and 7.

[0031] exist Figure 1 The diagram shows the rocker mechanism in the base circle phases of cams 18, 19, and 20 during the first operating state, while... Figure 2 In the second operating state, the exhaust main cam 18 is in the cam lift phase, while the exhaust secondary cam 19 and intake cam 20 are in the base circle phase. According to... Figure 3In the third operating state, the intake cam 20 is in the cam lift phase. Here, the exhaust master cam 18 and exhaust secondary cam 19 are in the base circle phase. In the cam lift phase, levers 1b, 1c, and 2b on each control side are actuated by picking up the cam lift, while they are not actuated in the base circle phase.

[0032] The coupling mechanisms 9, 10, and 11 are integrated into the valve-side levers 1a and 2a and the control-side levers 1b, 1c, and 2b in a space-saving manner. Figure 4 and Figure 6 A cross-section of the rocker arm device is shown, extending through the first coupling mechanism 9 and the third coupling mechanism 11 and through the associated actuators 12 and 14. The first coupling mechanism 9 and the third coupling mechanism 11 each have a cylindrical operating piston 9a, 11a and a cylindrical connecting piston 9b, 11b. The operating pistons 9a and 11a are movably disposed in axial through-holes 25 or 26 on the lever end regions 23 or 24 of the connecting side of the first lever 1a and the second lever 2a on the valve side, respectively, to facilitate switching. On the operating side of the first lever 1b and the third lever 2b, the corresponding connecting pistons 9b or 11b are movably received in axial holes 27 or 28, respectively.

[0033] The actuating pistons 9a and 11a are axially movable at their respective actuator ends via the corresponding actuators 12 and 14 in direct adjustment contact. They each contact their respective connecting pistons 9b and 11b at their other end ends. The latter are preloaded onto the corresponding actuating pistons 9a and 11a via spring mechanisms 29 and 30. Spring mechanisms 29 and 30 are coaxially arranged in holes 27 and 28 as helical pressure springs, respectively. The movement of the actuating pistons 9a and 11a is limited on the actuator side by sleeves 31 and 32 pressed into through holes 25 and 26, respectively, and by a stop 24a formed on the axial end side of the sleeve.

[0034] exist Figure 5 and Figure 7 The image shows a cross-section of the rocker arm assembly having a second cross-section extending through the second coupling mechanism 10 and the associated actuator 13. The second coupling mechanism 10 consists of a cylindrical connecting piston 10a (…). Figure 3The connecting piston 10a is movably disposed in the axial through-hole 33 of the second lever 1c on the operating side for switching purposes. The connecting piston 10a is axially movable at its end on the operating side via the actuator 13 in direct adjustment contact. This connecting piston is movable to connect to the axial through-hole 34 on the first lever 1a on the valve side. The through-hole 34 is designed as an axial through-hole. The connecting piston 10a is preloaded onto the actuator 13 by a spring mechanism 35. The spring mechanism 35 is coaxially disposed in the through-hole 34 as a helical pressure spring.

[0035] For coupling, such as in Figure 4 and Figure 7 As shown, connecting pistons 9b, 10b, and 11b are respectively in the unpivoted initial positions of levers 1a and 1b, 1a and 1c, or 2a and 2b on the corresponding valve side and operating side in the corresponding base circle phases of cams 18, 19, and 20. Figure 1 The pistons 9b, 10b, and 11b can be moved from the connecting end of the levers 1b and 2b on the corresponding operating side through holes 27 and 28, or through holes 33 on the second lever 1c on the operating side, and then into the corresponding through holes 25 and 26 on the levers 1a or 2a on the corresponding valve side, or into the hole 34 on the first lever 1a on the valve side. Here, the connecting pistons 9b, 10b, and 11b can be moved to the coupled position by the spring force of the corresponding pre-tightened spring mechanisms 29 and 30, or by overcoming the spring force of the spring mechanism 35. Here, the spring mechanism 35 is simultaneously pre-tightened for decoupling. Figure 5 and Figure 6 Decoupling is achieved by manipulating the corresponding actuators 12, 13, and 14 and moving the corresponding actuating pistons 9a, 11a and connecting piston 10a to overcome the spring forces of the corresponding spring mechanisms 29 and 30, or by contacting the corresponding connecting pistons 9b, 10b, and 11b through the spring force of the pre-tightened spring mechanism 35. Here, the connecting pistons 9b, 10a, and 11b are moved back into the corresponding holes 27, 28 or through hole 33, and the spring mechanisms 29 and 30 are pre-tightened to facilitate coupling.

[0036] Actuators 12, 13, and 14 are respectively implemented as electrically driven magnets or linear magnets. Figures 1 to 3These are housed in a common bracket 36 axially positioned between rocker arms 1 and 2, which is connected to the base plate 36a and the rocker arm shaft 3 via a first threaded connector 37. The bracket 36 has two arms 36b and 36c extending perpendicularly to the rocker arm shaft 3 from the base plate 36a. These arms are parallel to the rocker arms 1 and 2 and extend toward the camshaft 8, which is parallel to the rocker arm shaft 3. The arms 36b and 36c form cylindrical sleeves 38, 39, and 40, respectively, into which actuators 12, 13, and 14 are respectively mounted with electromagnetically linearly movable armatures 12a, 13a, and 14a. Figures 4 to 7 On the arms 36b and 36c, actuators 12, 13, and 14 can be respectively disposed in the sleeves (through holes 26, 27, and 28) at any radial distance relative to the rocker shaft 3 and simultaneously on the camshaft side of the rocker shaft 3 between the rocker shaft and the camshaft 8.

[0037] By energizing the stroke magnet, the corresponding armatures 12a, 13a, and 14a, with their connecting ends in adjusting contact with the corresponding coupling mechanisms 9, 10, and 11, can axially move out of their respective sleeves 38, 39, and 40 for switching purposes. By cutting off the energization, the actuators 12, 13, and 14 can be deactivated, and the corresponding armatures 12a, 13a, and 14a can move back into their respective sleeves 38, 39, and 40. To reset the armatures 12a, 13a, and 14a in the de-energized state, return spring mechanisms 12b, 13b, and 14b can be provided in the corresponding stroke magnet as shown. The bracket 36 forms the first sleeve 38 and the second sleeve 39 on the first arm 36b. The arm 36b, having sleeves 38 and 39, is located on the axially inner side of the second lever 1c on the operating side, away from the valve side of the first lever 1a. Here, sleeves 38 and 39 are axially inner opposite to the second lever 1c on the operating side. A first actuator 12 and a second actuator 13 are disposed in sleeves 38 and 39, each having a corresponding armature 12a and 13a for direct adjusting contact with the operating piston 9a or connecting piston 10a of the corresponding first coupling mechanism 9 or second coupling mechanism 10. The second arm 36c is constructed with a third sleeve 40 and is guided along the axially inner side of the second lever 2a on the valve side. Here, sleeve 40 is axially inner opposite to the second lever 2a on the valve side. On the second arm 36c, a third actuator 14 is disposed in the third sleeve 40, each having an armature 14a for direct adjusting contact with the operating piston 11a of the first or third coupling mechanism 11.

[0038] exist Figure 4 and Figure 5In the first switching state of the rocker arm device shown, actuators 12, 13, and 14 are in a deactivated state, meaning all three stroke magnets are not energized, and armatures 12a, 13a, and 14a are pushed back into their respective sleeves 38, 39, and 40. Here, the first lever 1a on the valve side is coupled to the first lever 1b on the operating side via the first coupling mechanism 9. Figure 4 And simultaneously decoupled from the second lever 1c on the operating side via the second coupling mechanism 10. Figure 5 Therefore, the second lever 1c is in its no-stroke state because the additional valve lift picked up from the second cam 19 is invalid. Figure 2 Here, only the full valve lift picked up by the first lever 1b on the control side on the first cam 18 is transmitted to the exhaust valves 4 and 5 via the first lever 1a on the valve side. Simultaneously, the second lever 2a on the valve side is coupled to the third lever 2b on the control side via the third coupling mechanism 11. Figure 4 Therefore, the intake valves 6 and 7 are operated by the second lever 2a on the valve side to achieve the full valve lift picked up by the first lever 1b on the operating side on the third cam 20. Figure 2 The deactivated actuators 12 and 14, with armatures 12a and 14a pushed back into sleeves 38 and 39, respectively, axially overlap at least partially with the end faces of the operating side of the first actuating piston (operating piston 9a) or the third actuating piston (operating piston 11a) pivoting with the first lever 1a or the second lever 2a on the valve side. Figure 4 and Figure 6 Thus, the first coupling mechanism 9 and the second coupling mechanism 11 can be continuously and without delay operated by the first actuator 12 and the third actuator 14. This can also be achieved by positioning the actuators 12 and 14 in the bracket 36 and the coupling mechanisms 9 and 11 in the levers 1a and 2a on the valve side close to the rocker shaft 3, so that the absolute movement of the pistons 9a and 11a during the pivoting motion of the levers 1a and 2a on the valve side is small even at full valve lift.

[0039] Because according to Figure 5 In the first switching state, the second actuator 13 is deactivated, and the second connecting piston 10a is moved to the decoupled position by the spring force of the associated spring mechanism 30. The second connecting piston, with its mushroom-shaped expanded actuator-side end 41, axially abuts against the first arm 36b of the bracket 36. The mushroom-shaped expanded end 41 of the second connecting piston 10a slides back and forth on the first arm 36b on the end side during the pivoting movement of the second lever 1c on the operating side. In this way, the second lever 1c on the operating side is prevented from dislodging from the through hole 33 on the bracket 36.

[0040] exist Figure 6In the second switching state of the rocker arm device shown, only the first actuator 12 and the third actuator 14 are activated. Here, by removing the armatures 12a and 14a, the first coupling mechanism 9 and the third coupling mechanism 11 move to the decoupled position, and the first lever 1a on the valve side is decoupled from the first lever 1b on the operating side, and the third lever 2a on the valve side is decoupled from the third lever 2b on the operating side. Because the second actuator 13 is deactivated, the second lever 1c on the operating side is decoupled from the first lever 1a on the valve side. This results in the first lever 1a and the second lever 2a on the valve side being deactivated. The deactivated first lever 1b and the deactivated third lever 2b on the operating side are in the no-stroke state because the full valve lift picked up by them on the first or second cams 18 and 19 is invalid. Figure 2 Therefore, the two rocker arms 1 and 2 are disconnected and the valve lift is not transmitted to the valves 4 and 5 or 6 and 7. Figure 2 In this way, cylinder deactivation is achieved in the second operating state of the rocker mechanism.

[0041] according to Figure 7 In the third switching state of the rocker arm mechanism, the second actuator 13 is activated while the first actuator 12 is deactivated. The armature 13a of the second actuator 13 is removed. Here, the first lever 1a on the valve side is coupled to the second lever 1c on the operating side via the second coupling mechanism 10, and the additional valve lift picked up by the second lever on the operating side on the second cam 19 is transmitted to the first lever on the valve side. Figure 3 Because the first lever 1a on the valve side is simultaneously coupled to the first lever 1b on the control side via the first coupling mechanism 9 ( Figure 4 Therefore, the full valve lift picked up by the first lever 1b on the control side and the first cam 18 is also transmitted to the first lever on the valve side. Figure 3 Here, exhaust valves 4 and 5 are controlled by the first lever 1a on the valve side with the full valve lift of the main cam 18 and the additional valve lift that can be engaged by the secondary cam 19.

[0042] Here, in the fourth switching state of the rocker arm mechanism, the first actuator 12 is activated, and the first lever 1a on the valve side is decoupled from the first lever 1b on the operating side via the first coupling mechanism 9. The first lever 1b on the operating side thus reaches its idle stroke. In this way, only the additional valve lift picked up by the second lever 1c on the operating side on the second cam 19 is transmitted to the exhaust valves 4 and 5 via the first lever 1a on the valve side. Figure 3 ).

[0043] Actuators 12, 13, and 14 with armatures 12a, 13a, and 14a, and coupling mechanisms 9, 10, and 11 are movably arranged parallel to the rocker axis 3 and transverse to the longitudinal axis of the rockers 1 and 2 in holes 27, 28, and 34 and through holes 25, 26, and 33, respectively, for switching purposes. In this way, the rockers can be switched by a so-called lateral locking that saves structural space, which simultaneously enables the coupling mechanisms 9, 10, and 11 to be arranged close to the rocker axis.

[0044] Joysticks 1 and 2 can be individually operated via actuators 12, 13, or 14. The travel magnets of actuators 12, 13, and 14 can be controlled by an electronic control unit (not shown). For this purpose, a central contact, particularly a center plug, is integrated into the joystick assembly. An interface for engine control (not shown) can be located on the exterior of the cylinder head of the internal combustion engine. The travel magnets can be activated via engine control switching commands, i.e., so-called bus signals. The integrated electronic unit is responsible for calculating the precise energizing timing of the travel magnets. Furthermore, the integrated electronic unit also determines which of the various travel magnets should be operated.

[0045] according to Figure 8 The rocker arm assembly can be directly fixed to the cylinder head 43 of the internal combustion engine via the rocker arm shaft 3 and the second threaded connector 42 in a simple manner. For this purpose, a plurality of screws of the threaded connector 42 are guided through radial through holes 44 and 45 on the rocker arm shaft 3 in the region of the base plate 36a of the bracket 36 and tightened into threaded holes 46 and 47 on the cylinder head 43. Figures 1 to 3 and Figure 8 It is also conceivable that the rocker shaft 3 and the bracket 36 are fixed to the cylinder head 43 by the first or second threaded connectors 37 and 42. Figures 1 to 3 ).

[0046] according to Figures 4 to 8 The system is equipped with return spring mechanisms 48, 49, and 50, which preload the corresponding valve-side levers 1a and 2a and the corresponding operating-side levers 1b, 1c, and 2b to their unpivoted initial positions. Return spring mechanisms 48, 49, and 50 are used to return the levers to their initial positions in a decoupled state. The first return spring mechanism 48 and the second return spring mechanism 49 are respectively configured to act between the first lever 1a on the valve side and the first lever 1b or the second lever 1c on the operating side, and the third return spring mechanism 50 is configured to act between the second lever 2a on the valve side and the third lever 2b on the operating side.

[0047] The return spring mechanisms 48, 49, and 50 are designed as torsion springs or rotary springs, preferably as torsion springs with legs. The return spring mechanisms are coil-shaped and coaxially arranged relative to the rocker shaft 3 in the axially opposed annular gaps 51, 52 or 53, 54 or 55, 56 on the longitudinal sides of the levers 1a and 2a on the respective valve sides and the levers 1b, 1c, and 2b on the operating sides of these levers, respectively. The return spring mechanisms are clamped in the pivoting direction on the levers 1a and 2a on the respective valve sides with one spring end and on the levers 1b, 1c, and 2b on the respective operating sides with the other spring end. The first return spring mechanism 48 is accommodated in the first gap 51 on the longitudinal side of the first lever 1a on the valve side, away from the second lever 1c on the operating side, and in the second gap 52 on the longitudinal side of the first lever 1b on the operating side, aligned with the first gap. The second return spring mechanism 49 is disposed in a third gap 53 on the longitudinal side of the first lever 1a on the valve side, which is axially inward from the first lever 1b on the operating side, and in a fourth gap 54 on the longitudinal side of the second lever 1c on the operating side, which corresponds to the third gap. To accommodate the third return spring mechanism 50, a fifth gap 55 is provided on the longitudinal side of the second lever 2a on the valve side, which corresponds to a sixth gap 56 on the longitudinal side of the third lever 2b on the operating side. Here, the return spring mechanisms 48, 49, and 50 are guided radially and axially in the gaps 51, 52 or 53, 54 or 55, 56, respectively.

[0048] List of reference numerals 1. First joystick 1a First lever on the valve side 1b control side first lever 1c control side second lever 2. Second joystick 2a The second lever on the valve side The third lever on the 2b control side 3 joystick axes 4 ventilation valves 5 ventilation valves 6 air exchange valves 7 ventilation valves 8 Camshafts 9. Coupling mechanism 9a manipulating piston 9b connecting piston 10 Coupling Mechanism 10a connecting piston 11 Coupling Mechanism 11a Operating Piston 11b connecting piston 12 actuators 12a armature 12b return spring mechanism 13 actuators 13a armature 13b Reset Spring Mechanism 14 actuators 14a armature 14b Return Spring Mechanism 15 Cam Roller 16 Cam Roller 17 Cam Roller 18 Cams, Main Cams 19-cam, secondary cam 20 Cam 21 valve contacts 22 valve contacts 23 Lever end area 24 Lever end area 25 through holes 26 through holes 27 holes 28 holes 29 Spring Mechanism 30 Spring Mechanism 31 casings 31a Stop Section 32 sleeves 32a stop section 33 through holes 34 holes 35 Spring Mechanism 36 stents 36a substrate 36b arm 36C arm 37 Threaded connector 38 sleeves 39 casing 40 sleeves 41 end 42 threaded connector 43 cylinder head 44 through holes 45 through hole 46 threaded hole 47 threaded hole 48. Reset Spring Mechanism 49. Reset Spring Mechanism 50 Reset Spring Mechanism 51. Gap 52 voids 53. Void 54 gaps 55 gap 56. Void

Claims

1. A rocker arm device for a valve mechanism of an internal combustion engine, the rocker arm device having at least one rocker arm, the rocker arm being pivotally mounted on a rocker arm shaft (3) by a first lever (1a) on the valve side for operating at least one valve (4, 5) of the internal combustion engine and by two levers (1b, 1c) on the operating side for pivotally driven movement, wherein, The valve-side first lever (1a), the operating-side first lever (1b), and the operating-side second lever (1c) are pivotally supported on the rocker shaft (3). To switch the rocker (1), the operating-side first lever (1b) can be coupled to the valve-side first lever (1a) via a first coupling mechanism (9) to transmit a first lift motion for valve operation, and the operating-side second lever (1c) can be coupled to the valve-side first lever (1a) via a second coupling mechanism (10) to transmit a second lift motion for valve operation. The second rocker (2) is located adjacent to the first rocker (1) on the rocker shaft (3), i.e., the first rocker (1) and the second rocker (2) are located on a common rocker shaft (3). The second rocker (2) is positioned as a valve-side second lever (2a) for operating at least one valve (6, 7) of the internal combustion engine and as a... The third lever (2b) on the control side, which is pivotally driven, is pivotally mounted on the rocker shaft (3). The second lever (2a) on the valve side and the third lever (2b) on the control side are pivotally supported on the rocker shaft (3). In order to switch the second rocker (2), the third lever (2b) on the control side can be connected to the second lever (2a) on the valve side via a third coupling mechanism (11) to transmit a third lift motion for valve control. The first coupling mechanism (9), the second coupling mechanism (10), and the third coupling mechanism (11) are each equipped with an actuator (12, 13, 14) for switching. The actuators (12, 13, 14) are at least partially integrated into a bracket (36) connected to the rocker shaft (3) and are arranged radially relative to the rocker shaft (3). The bracket (36) is axially arranged between the first rocker (1) and the second rocker (2).

2. The rocker arm device according to claim 1, characterized in that, The first lever (1a) on the valve side makes valve contact with at least one exhaust valve (4, 5) of the internal combustion engine, and the second lever (2a) on the valve side makes valve contact with at least one intake valve (6, 7).

3. The rocker arm device according to claim 1, characterized in that, The first lever (1b) on the control side contacts the first cam (18) of the camshaft (8) of the internal combustion engine to pick up the full valve lift for valve control, and the second lever (1c) on the control side contacts the second cam (19) of the camshaft (8) to pick up the additional valve lift for valve control, and the third lever (2b) on the control side contacts the third cam (20) of the camshaft (8) to pick up the full valve lift for valve control.

4. The rocker arm device according to claim 1, characterized in that, in, The actuators (12, 13, 14) are designed as electric solenoids, each having an armature (12a, 13a, 14a) that can move linearly. The first coupling mechanism (9), the second coupling mechanism (10), and the third coupling mechanism (11) can be switched by moving the armatures in direct adjustment contact.

5. The rocker arm device according to claim 1, characterized in that, The first coupling mechanism (9), the second coupling mechanism (10), and the third coupling mechanism (11) are movably disposed in the axial holes on the lever on the valve side and the lever on the corresponding operating side, so as to switch between them.

6. The rocker device according to any one of claims 1 to 5, characterized in that, The coupling mechanism and at least one actuator (12, 13, 14) movably integrated into the lever on the valve side or the lever on the control side for switching are configured such that, when the lever on the respective valve side or the lever on the respective control side pivots relative to the respective actuator (12, 13, 14), at least a partial overlap in the direction of movement between the coupling mechanism and the actuator (12, 13, 14) is ensured for switching.

7. The rocker device according to any one of claims 1 to 5, characterized in that, At least a second lever (1c) movable on the control side for switching and at least one actuator integrated in the bracket (36) for maneuvering of the lever on the control side are arranged such that when the second lever (1c) on the control side pivots relative to the bracket (36), the connecting piston (10a) abuts against the bracket (36) on the actuator side in the direction of movement in the decoupled state.

8. The rocker arm device according to any one of claims 1 to 5, characterized in that, A return spring mechanism (48, 49, 50) is provided, which preloads at least one lever on the operating side and the corresponding lever on the valve side to their unpivoted initial positions relative to each other in the pivoting direction. Axially aligned opposing gaps are provided on the corresponding lever on the operating side and on the corresponding lever on the valve side on the longitudinal side of the corresponding axially opposed lever. The return spring mechanism (48, 49, 50) is at least partially disposed in the gaps and is clamped in the pivoting direction.

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