Rocker system with cylinder deactivation and selective valve lift capabilities

Abstract

The internal combustion engine system includes an engine having a plurality of pistons housed in each of a plurality of cylinders. A valve train is provided for opening and closing intake and exhaust valves of the cylinders during nominal engine operation. The valve train is also configured for cylinder deactivation and to provide one or more selected lift profiles for opening and closing the intake and / or exhaust valves.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 239,539, filed September 1, 2021, which is incorporated herein by reference. [Background technology]

[0002] The present invention relates to internal combustion engine systems and, more particularly, but not limited to, valve trains for internal combustion engines including rocker systems with cylinder deactivation and selective valve lift capabilities.

[0003] Cylinder deactivation at low engine loads can be achieved by keeping the intake and exhaust valves of some of the engine cylinders closed during certain operating conditions to conserve fuel and operate at increased efficiency. Cylinder deactivation typically requires switching the cam profile operating on the deactivated cylinders from a nominal profile to a zero profile. Compression release braking can be achieved by a cam profile that opens the exhaust valve for braking lift during the corresponding crank angle that provides compression release from the cylinder. Thus, there is a continuing need for further contributions in this field of technology. Summary of the Invention

[0004] In one embodiment of the present application, a rocker system for an internal combustion engine is disclosed. The rocker system includes at least one input rocker lever rotatable about an engine component in response to motion received from at least one camshaft lobe of a camshaft. The rocker system also includes at least one output rocker lever rotatable about the engine component. The at least one output rocker lever is configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine. The rocker system also includes at least one valve lift switch operable to connect the at least one input rocker lever and the at least one output rocker lever to each other and to disconnect the at least one input rocker lever and the at least one output rocker lever from each other to transfer motion from the at least one camshaft lobe to the at least one exhaust valve or the at least one intake valve. The rocker system further includes at least one additional input rocker lever or output rocker lever connectable to the at least one output rocker lever by the at least one valve lift switch.

[0005] In another embodiment, a rocker system for an internal combustion engine is disclosed. The rocker system includes a first input rocker lever rotatable about an engine component in response to motion received from a first camshaft lobe of a camshaft, and a second input rocker lever rotatable about the engine component in response to motion received from a second camshaft lobe of the camshaft. The rocker system includes at least one output rocker lever rotatable about the engine component, the at least one output rocker lever configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine. The rocker system includes a first valve lift switch and a second valve lift switch. The first valve lift switch is operable to connect the first input rocker lever to the at least one output rocker lever to transfer motion from the first camshaft lobe to the at least one exhaust valve or at least one intake valve. The second valve lift switch is operable to connect the second input rocker lever to the at least one output rocker lever to transfer motion from the second camshaft lobe to the at least one exhaust valve or the at least one intake valve. The first and second valve lift switches are operable to disconnect the respective first and second input rocker levers from the at least one output rocker lever such that motion from the first and second camshaft lobes is not transferred to the at least one output rocker lever.

[0006] This Summary is provided to introduce a selection of concepts that are further described below in exemplary embodiments. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. Further embodiments, forms, objects, features, advantages, aspects, and benefits will become apparent from the following description and drawings. [Brief description of the drawings]

[0007] [Figure 1]FIG. 1 is a schematic diagram of one embodiment of an internal combustion engine system having a valvetrain that provides alternating valve lift and cylinder deactivation capabilities for at least one cylinder. [Diagram 2] 2 is a diagram and schematic diagram of one embodiment of a cylinder and a schematic valve actuation mechanism of the internal combustion engine system of FIG. 1; [Diagram 3] 2 is a graphical representation of exemplary lift profiles of intake and exhaust valves of a cylinder of the internal combustion engine system of FIG. 1 during a standard operating mode and during an exemplary braking operating mode. [Figure 4] FIG. 2 is a perspective view showing the valve actuation system and the intake and exhaust valves of the cylinder of the internal combustion engine system of FIG. 1. [Diagram 5] FIG. 5 is an elevational view of the valve actuation system and intake and exhaust valves of FIG. [Figure 6] FIG. 5 is a perspective view of one embodiment of a rocker system of the valve actuation system of FIG. [Figure 7] FIG. 7 is a plan view of the rocker system of FIG. 6. [Figure 8] FIG. 7 is an elevational view of the rocker system of FIG. [Figure 9] 7A-7C are cross-sectional views of the rocker system of FIG. 6 illustrating standard lift mode, cylinder deactivation mode, and auxiliary lift mode of operation, respectively. [Figure 10] 7A-7C are cross-sectional views of the rocker system of FIG. 6 illustrating standard lift mode, cylinder deactivation mode, and auxiliary lift mode of operation, respectively. [Figure 11] 7A-7C are cross-sectional views of the rocker system of FIG. 6 illustrating standard lift mode, cylinder deactivation mode, and auxiliary lift mode of operation, respectively. [Figure 12] FIG. 2 is an elevational view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Figure 13] FIG. 13 is a plan view of the rocker system of FIG. 12. [Figure 14] 13A-13C are cross-sectional views of the rocker system of FIG. 12 showing standard lift mode, cylinder deactivation mode, and braking operation mode, respectively. [Figure 15]13A-13C are cross-sectional views of the rocker system of FIG. 12 showing standard lift mode, cylinder deactivation mode, and braking operation mode, respectively. [Figure 16] 13A-13C are cross-sectional views of the rocker system of FIG. 12 showing standard lift mode, cylinder deactivation mode, and braking operation mode, respectively. [Figure 17] 13A to 13C are cross-sectional views showing a method of assembling the rocker system of FIG. 12. [Figure 18] 13A to 13C are cross-sectional views showing a method of assembling the rocker system of FIG. 12. [Figure 19] FIG. 2 is a perspective view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. [Figure 20] 20A-20C are cross-sectional views of the rocker system of FIG. 19 showing standard lift mode, cylinder deactivation mode, and braking mode of operation, respectively. [Figure 21] 20A-20C are cross-sectional views of the rocker system of FIG. 19 showing standard lift mode, cylinder deactivation mode, and braking mode of operation, respectively. [Figure 22] 20A-20C are cross-sectional views of the rocker system of FIG. 19 showing standard lift mode, cylinder deactivation mode, and braking mode of operation, respectively. [Diagram 23] FIG. 20 is another cross-sectional view of the rocker system of FIG. 19 showing the stop pin. [Figure 24] FIG. 24 is a perspective view of the rocker system of FIG. 23 showing the stop pin. [Diagram 25] FIG. 2 is a perspective view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. [Figure 26] FIG. 26 is a plan view of the rocker system of FIG. 25. [Figure 27] FIG. 26 is an elevational view of the rocker system of FIG. [Figure 28] FIG. 26 is a cross-sectional view of the rocker system of FIG. [Figure 29] FIG. 2 is a perspective view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. [Diagram 30] FIG. 30 is a cross-sectional view of the rocker system of FIG. 29. [Diagram 31]FIG. 2 is a plan view of another embodiment of an intake side rocker system and an exhaust side rocker system for two cylinders of the internal combustion engine of FIG. 1. [Diagram 32] FIG. 32 is a cross-sectional view of the exhaust side rocker system of FIG. 31. [Diagram 33] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Diagram 35] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Diagram 36] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Figure 37] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Figure 38] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Figure 39] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Diagram 40] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. [Diagram 41] FIG. 2 is a plan view of another embodiment of a rocker system for a cylinder of the internal combustion engine of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] While the present invention may take many different forms to promote understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the embodiments. It will nevertheless be understood that no limitation of the scope of the invention is intended thereby. Any changes and further modifications of the described embodiments, and any further applications of the principles of the invention as described herein, are contemplated as would normally occur to one skilled in the art to which the invention pertains.

[0009] 1-41, embodiments of the present application include a unique system that operates one or more cylinders 14 of an internal combustion engine 12 using one of: cylinder deactivation for low load efficiency improvement, standard or nominal lift for the intake and / or exhaust valves of the cylinders 14, and selective lift of one or more of the cylinders 14, for example to provide compression release braking or swirl to the corresponding cylinders 14. Other embodiments include a system for an internal combustion engine system 10 with a valvetrain configured to enable one or more cylinders 14 to operate under nominal exhaust and intake valve lift, cylinder deactivation, and / or selective intake and / or exhaust valve lift that varies lift height and / or lift timing from its standard lift.

[0010] In one embodiment, a rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 for an internal combustion engine 12 is disclosed herein in accordance with one embodiment of the present disclosure. The rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 includes at least one input rocker lever 104, 106, 108, 304, 306, 308, 504, 506, 508, 706, 806, 808, 906, 908, 908a, 908b, 908c, 908c of the camshaft 92, 94. 808, 904, 906, 994, 996, 1010, 1110, 1202, 1310, 1410, 1412, 1510, 1512, 1514, 1610, 1612, 1710, 1712, and at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 rotatable about the engine component 120. At least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 is configured to control the opening and closing of at least one exhaust valve 24 or at least one intake valve 22 associated with a cylinder 14 of the internal combustion engine 12.The rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 includes at least one input rocker lever 104, 106, 108, 30 for transferring motion from at least one camshaft lobe 92a, 94a, 92b, 94b, 92c, 94c to at least one exhaust valve 24 or at least one intake valve 22. 4, 306, 308, 504, 506, 508, 706, 806, 808, 904, 906, 994, 996, 1010, 1110, 1202, 1310, 1410, 1412, 1510, 1512, 1514, 1610, 1612, 1710, 1712 and at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 13 04, 1402, 1502, 1504, 1602, 1702, 1802 are connected to each other, and at least one input rocker lever 104, 106, 108, 304, 306, 308, 504, 506, 508, 706, 806, 808, 904, 906, 994, 996, 1010, 1110, 1202, 1310, 1410, 1412, 1510, 1512, 1514, 1610, 1612, 1710, 1712, and a few and at least one valve lift switch 150, 200, 350, 400, 550, 600, 750, 850, 870, 920, 940 operable to disconnect at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 from each other.The rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 includes at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 904, 906, 908, 909, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 921, 922, 923, 924, 925, 926, 927, 928, 929, 930, 931, 932, 933, 934, 935, 936, 937, 938, 939, 940, 941, 942, 943, 944, 945, 946, 947, 948, 949, 950, 951, 952, 953, 954, 955, 956, 957, 958, 960, 961, 962, 963, 964, 965, 966, 967, 968, 970, 970, 971, 972, 973, 974, 975, 976, 977, 978, 980, 981, 982, 983, 9 92, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802.

[0011] According to another embodiment of the present disclosure, a rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 for an internal combustion engine 12 is disclosed. The rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 includes a first input rocker lever 104, 304, 504, 706, 806, 904, 994, 1010, 1110, 1202, 1310, 1410, 1510, 1610, 1710 rotatable about the engine component 120 in response to motion received from a first camshaft lobe 92a, 94a of the camshafts 92, 94 and a second camshaft lobe 92b of the camshafts 92, 94. a second input rocker lever 106, 108, 306, 308, 506, 508, 808, 906, 996, 1412, 1512, 1514, 1612, 1712 rotatable about the engine component 120 in response to motion received from the input rocker lever 106, 108, 306, 308, 506, 508, 808, 906, 996, 1412, 1512, 1514, 1612, 1712, and at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 rotatable about the engine component 120. At least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 is configured to control the opening and closing of at least one exhaust valve 24 or at least one intake valve 22 associated with a cylinder 14 of the internal combustion engine 12. The rocker system 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 also includes a first valve lift switch 150, 350, 550, 750, 850, 920 and a second valve lift switch 200, 400, 600, 870, 940.The first valve lift switch 150, 350, 550, 750, 850, 920 is operable to connect the first input rocker lever 104, 304, 504, 706, 806, 904, 994, 1010, 1110, 1202, 1310, 1410, 1510, 1610, 1710 to at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 to transmit motion from the first camshaft lobe 92a, 94a to at least one exhaust valve 24 or at least one intake valve 22. The second valve lift switch 200, 400, 600, 870, 940 is operable to connect the second input rocker lever 106, 108, 306, 308, 506, 508, 808, 906, 996, 1412, 1512, 1514, 1612, 1712 to at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802 to transmit motion from the second camshaft lobe 92b, 94b to at least one exhaust valve 24 or at least one intake valve 22.The first valve lift switch 150, 350, 550, 750, 850, 920 and the second valve lift switch 200, 400, 600, 870, 940 respectively couple the first input rocker lever 104, 304, 504, 706, 806, 904, 994, 1010, 1110, 1202, 1310, 1410, 1510, 1610, 1710 and the second input rocker lever 106, 108, 306, 308, 506, 508, 808, 906, 996, 1412, 1512, 1514, 1612, 1712 to at least one output rocker lever 102, 302, 502, 702 , 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802, such that motion from the first camshaft lobe 92a, 94a and the second camshaft lobe 92b, 94b is not transmitted to the at least one output rocker lever 102, 302, 502, 702, 704, 802, 804, 902, 992, 1002, 1004, 1102, 1302, 1304, 1402, 1502, 1504, 1602, 1702, 1802.

[0012] With reference to FIG. 1, an internal combustion engine system 10 is shown, including, for example, an internal combustion engine 12. Any engine type is contemplated, including compression ignition, spark ignition, and combinations thereof. The engine 12 may include a plurality of cylinders 14. FIG. 1 illustrates, for illustrative purposes only, a plurality of cylinders 14 in an arrangement including six cylinders 14 in a series arrangement. Any number of cylinders and any arrangement of cylinders suitable for use in the internal combustion engine 12 may be utilized. The number of cylinders 14 that may be utilized may range from, for example, two to eighteen cylinders, or more. Additionally, the following description may refer to one of the cylinders 14. It should be appreciated that corresponding features with respect to a cylinder 14 described in FIG. 2 and elsewhere herein may be present in all or a subset of the other cylinders 14 of the engine 12, unless otherwise noted.

[0013] As discussed herein, the internal combustion engine system 10 includes a valve actuation system with a rocker system, embodiments of which discussed further below are configured to open and close the intake and / or exhaust valves of associated cylinders 14 of the engine 12. The rocker system includes at least one output rocker lever selectively connectable to one or more input rocker levers to achieve functional operating modes. Functional operating modes that can be achieved by the rocker system of the present disclosure include, for example, nominal or standard intake and exhaust valve operation, Miller cycle intake valve operation, four-stroke engine compression braking exhaust valve operation, intake and / or exhaust valve cylinder deactivation, two-stroke engine compression braking of intake and exhaust valves, variable swirl intake valve operation, and / or dynamic skip fire.

[0014] An exemplary embodiment of a cylinder 14 is shown in FIG. 2, with it being understood that any suitable cylinder embodiment is contemplated herein. The cylinder 14 typically contains a piston 16 operatively attached to a crankshaft 18 that rotates by the piston 16 moving reciprocally within a combustion chamber 28 of the cylinder 14. Within a cylinder head 20 of the cylinder 14 are at least one intake valve 22, at least one exhaust valve 24, and, in certain embodiments, a fuel injector 26 that provides fuel to a combustion chamber 28 formed by the cylinder 14 between the piston 16 and the cylinder head 20. In other embodiments, fuel may be provided to the combustion chamber 28 by port injection or by injection within the intake system upstream of the combustion chamber 28. Additionally, in the following discussion, each cylinder 14 includes two intake valves 22 and two exhaust valves 24, although these are not required in all embodiments.

[0015] The term "four strokes" herein refers to the four strokes - intake, compression, combustion, and exhaust - that the piston 16 completes in a combustion cycle during two separate revolutions of the engine's crankshaft 18. A stroke begins at top dead center (TDC) when the piston 16 is at the top of the cylinder head 20 of the cylinder 14, or at bottom dead center (BDC) when the piston 16 reaches its lowest point in the cylinder 14.

[0016] 3, an exemplary nominal or standard intake and exhaust valve opening and closing profile during a combustion cycle for intake valve (IV1) and exhaust valve (EV1) is shown. During the intake stroke of IV1, piston 16 leaves cylinder head 20 of cylinder 14 and descends to the bottom of the cylinder (not shown), thereby reducing pressure in combustion chamber 28 of cylinder 14. A combustion charge is created in combustion chamber 28 by drawing air in through intake valve 22 when intake valve 22 opens.

[0017] Fuel from the fuel injectors 26 may be supplied, for example, by a high pressure common rail system 30 (FIG. 1) connected to a fuel tank 32. Fuel from the fuel tank 32 is drawn by a fuel pump (not shown) and delivered to the common rail fuel system 30. Fuel delivered from the fuel pump is stored in the common rail fuel system 30, and the stored fuel is delivered through fuel lines 34 to the fuel injectors 26 of each cylinder 14. The stored fuel in the common rail system may be pressurized to increase and control the fuel pressure of the fuel delivered to the combustion chamber 28 of each cylinder 14. However, as noted above, any type of fuel delivery system is contemplated.

[0018] During the compression stroke in the standard operating mode, the intake valve 22 and exhaust valve 24 are closed, as shown by IV1 and EV1 in FIG. 3. As the piston 16 moves back towards TDC, fuel is injected into the compressed air in a main injection event near TDC, and after a short delay, the compressed mixture is ignited in the combustion chamber 28. If the engine 12 is a diesel engine, this results in ignition of the combustion charge. The ignition of the air and fuel causes a sudden increase in pressure in the combustion chamber 28, which is applied to the piston 16 during the combustion stroke towards BDC. The combustion phasing in the combustion chamber 28 is calibrated so that the increase in pressure in the combustion chamber 28 pushes the piston 16, which provides a net positive force / work / power.

[0019] During the exhaust stroke, the piston 16 moves back toward TDC while the exhaust valve 24 opens, as shown by EV1 in Figure 3. This action expels combustion products from the combustion of fuel in the combustion chamber 28 and expels the spent mixture (exhaust gases) out through the exhaust valve 24. The next combustion cycle occurs using these same intake and exhaust valve opening and closing profiles, unless cylinder deactivation or alternating valve lift conditions are required, as discussed further below.

[0020] 1, intake air flows through an intake passage 36 and an intake manifold 38 before reaching the intake valve 22. The intake passage 36 may be connected to a compressor 40a and an intake throttle 42 of a turbocharger 40. The intake air may be cleaned by an air cleaner (not shown), compressed by the compressor 40a, and then drawn into the combustion chamber 28 through the intake throttle 42. The intake throttle 42 may be controlled to affect the flow of air into the cylinder 14.

[0021] The intake passage 36 may further include an optional cooler 44 provided downstream of the compressor 40a. In one example, the cooler 44 may be a charge air cooler (CAC). In this example, the compressor 40a may increase the temperature and pressure of the intake air, while the CAC 44 may increase the charge density to provide more air to the cylinders. In another example, the cooler 44 may be a low temperature aftercooler (LTA). The CAC 44 uses air as a cooling medium, while the LTA uses a refrigerant as a cooling medium.

[0022] Exhaust gases exit the combustion chamber 28 into the exhaust passage 46 from an exhaust manifold 48 that connects the cylinder 14 to the exhaust passage 46. The exhaust passage 46 is connected to a turbine 40b of the turbocharger 40 and a wastegate 50, which in turn is connected to an aftertreatment system 52. The exhaust gases exiting the combustion chamber 28 drive the turbine 40b to rotate. The wastegate 50 is a device that allows a portion of the exhaust gases to bypass the turbine 40b through a passage 54. The wastegate 50 may include a control valve 56, which may be an open / closed (two-position) type valve, or a full authority valve that allows control of the bypass flow rate, or anything in between. The exhaust passage 46 may also or alternatively include an exhaust throttle 58 to regulate the flow rate of exhaust gases through the exhaust passage 46. The exhaust gases, which may be a combination of the bypass flow rate and the turbine flow rate, then enter the aftertreatment system 52. Other embodiments contemplate variable inlet turbines, turbine-less systems, and / or compressor-less systems.

[0023] Optionally, a portion of the exhaust gases can be recirculated into the intake system via an EGR passage (not shown). The EGR passage can connect the exhaust passage upstream of the turbine 40b to the intake passage 36 downstream of the intake throttle 42. Alternatively or additionally, a low pressure EGR system (not shown) can be provided downstream of the turbine 40b and upstream of the compressor 40a. An EGR valve can be provided to regulate the flow of EGR through the EGR passage. The EGR passage can further be provided with an EGR cooler and a bypass around the EGR cooler.

[0024] The aftertreatment system 52 may include one or more devices useful for handling and / or removing materials from the exhaust gas, which may be harmful components including carbon monoxide, nitric oxide, nitrogen dioxide, hydrocarbons, and / or soot in the exhaust gas. In some examples, the aftertreatment system 52 may include at least one of a catalyst device and a particulate filter. The catalyst device may be a diesel oxidation catalyst (DOC) device, an ammonia oxidation (AMOX) catalyst device, a selective catalytic reduction (SCR) device, a three-way catalyst (TWC), a lean NOX trap (LNT), etc. The reduction catalyst may include any suitable reduction catalyst (e.g., a urea selective reduction catalyst). The particulate filter may be a diesel particulate filter (DPF), a partial flow particulate filter (PFF), etc. The PFF functions to trap particulate matter in a portion of the flow, as opposed to the entire amount of exhaust gas passing through the particulate filter.

[0025] A controller 80 is provided to receive data as input from various sensors and send command signals as output to various actuators. Some of the various sensors and actuators that may be employed are described in detail below. The controller 80 may include, for example, a processor, memory, a clock, and input / output (I / O) interfaces.

[0026] The system 10 includes various sensors, such as an intake manifold pressure / temperature sensor 70, an exhaust manifold pressure / temperature sensor 72, one or more aftertreatment sensors 74 (differential pressure sensors, temperature sensors, pressure sensors, composition sensors, etc.), engine sensors 76 (which may detect the air / fuel ratio of the mixture delivered to the combustion chamber, the crank angle, the rotational speed of the crankshaft, etc.), and a fuel sensor 78 for detecting fuel pressure and / or other characteristics of the fuel, the common rail 38, and / or the fuel injectors 26. Any other sensors known in the art of engine systems are contemplated.

[0027] System 10 may also include various actuators for opening and closing intake valve 22, for opening and closing exhaust valve 24, for injecting fuel from fuel injector 26, for opening and closing wastegate valve 56, for intake throttle 42, and / or for exhaust throttle 58. Although actuators are not illustrated in FIG. 1, one skilled in the art would know how to implement the mechanisms necessary for each of the components to perform its intended function. Additionally, in one embodiment, actuators for opening and closing intake valve 22 and exhaust valve 24 are provided as part of a valve actuation (VA) system 90 as shown generally in FIG. 2.

[0028] 4-11, further details are shown regarding one embodiment of a VA system 90 that is applicable to provide cylinder deactivation of one or more of the cylinders 14 under cylinder deactivation conditions and / or alternate lift profiles of the intake and / or exhaust valves of one or more of the cylinders 14 in addition to the standard lift profiles discussed above. FIGS. 4-5 show a first VA system 90a on the intake side and a second VA system 90b on the exhaust side, which may be collectively and individually referred to herein as VA system 90. The VA system 90 may be provided for operation of one or both of the intake valves 22, for operation of one or both of the exhaust valves 24, for operation of one of the intake valves 22 and one of the exhaust valves 24, or for operation of all of the intake valves 22 and exhaust valves 24. Additionally, the VA system 90a may provide one or more lift profiles of the intake valves 22 that are different from one or more lift profiles of the exhaust valves 24.

[0029] Specifically, VA system 90a includes a rocker system 100a configured to engage a lobe of the intake camshaft 92 along one or more of the cylinders 14. Alternatively or additionally, VA system 90b may include the same, similar, or different rocker system 100b configured to engage a lobe of the exhaust camshaft 94 along one or more of the cylinders 14. Rocker systems 100a, 100b may be referred to herein individually or collectively as rocker systems 100.

[0030] In the illustrated embodiment, the camshaft 92 includes three camshaft lobes 92a, 92b, 92c that provide at least two different valve lift profiles for the intake valves 22, and the camshaft 94 includes three camshaft lobes 94a, 94b, 94c that provide at least two different valve lift profiles for the exhaust valves 94. In other embodiments, only two lobes or four or more lobes on one or both of the camshafts 92, 94 are contemplated. The three camshaft lobes on each camshaft in the illustrated embodiment can provide, for example, an associated nominal or standard lift profile for the associated valve 22, 24, as well as one or more auxiliary lift profiles for the valves 22, 24, that differ from the standard lift profile in height and / or timing of the valve lift from its respective valve seat.

[0031] 6-8, the rocker system 100 includes an output rocker lever 102, a first input rocker lever 104, a second input rocker lever 106, and a third input rocker lever 108, each rotatably mounted in a side-by-side relationship to an engine component 120, such as a rocker shaft. The first input rocker lever 104 includes a first roller 110 that directly or indirectly contacts a corresponding camshaft lobe 92a, 94a. The second input rocker lever 106 includes a second roller 112 that directly or indirectly contacts a corresponding camshaft lobe 92b, 94b. The third input rocker lever 108 includes a third roller 114 that directly or indirectly contacts a corresponding camshaft lobe 92c, 94c.

[0032] As discussed further below, one or more of the input rocker levers 104, 106, 108 can be controlled to be selectively connectable with the output rocker lever 102 to transfer motion from the respective camshaft lobes 92a, 94a, 92b, 94b, 92c, 94c to the connected ones of the intake valves 22 or exhaust valves 24. Additionally, the input rocker levers 104, 106, 108 can be controlled to be selectively disconnected from the output rocker lever 102 such that no valve lift is provided during cylinder deactivation. Controllable connection and disconnection of the output rocker 102 to the input rockers 104, 106, and / or 108 can be effected by engagement of the output rocker 102 to the input rockers 104, 106, and / or 108, by engagement of the input rockers 104, 106, and / or 108 to the output rocker 102, and combinations thereof.

[0033] The biasing mechanism 122 includes springs 124, 126, 128, each of which contacts the output rocker lever 102 and the input rocker levers 104, 106, 108, respectively, to bias the corresponding rollers 110, 112, 114 into direct or indirect contact with the respective camshaft lobes 92a, 94a, 92b, 94b, 96a, 96c. Also illustrated are hydraulic lash adjusters 130, 132 connected to the respective arms 102a, 102b of the output rocker lever 102 and also to the corresponding ones of the intake valves 22 or exhaust valves 24. The lash adjusters 130, 132 could also be mechanical lash adjusters. In the illustrated embodiment, the biasing mechanism 122 is positioned on the side of the rocker system 100 opposite the hydraulic lash adjusters 130, 132, although such positioning is not required.

[0034] In alternative embodiments, adjustment screws or elephant feet may be provided instead of or in addition to the lash adjusters 130, 132. A rocker seat 134 for mounting to the cylinder head 20 may also be provided, although embodiments without the rocker seat 134 are contemplated. Additionally, embodiments without a rocker shaft are contemplated, in which the rocker lever can mount about any suitable engine component 120, such as an end pivot integrated into the cylinder head on which the rocker lever mounts.

[0035] The rocker system 100 includes a first valve lift switch 150 that is controlled to selectively connect and disconnect the first input rocker lever 104 and the output rocker lever 102 from one another to transfer or prevent the transfer of motion between the associated camshaft lobes 92a, 94a and the connected ones of the intake valves 22 and / or exhaust valves 24. The rocker system 100 also includes a second valve lift switch 200 that is controlled to selectively connect and disconnect one or both of the second input rocker lever 106 and the third input rocker lever 108 from the output rocker lever 102 to transfer or prevent the transfer of motion between the associated camshaft lobes 92b, 94b, 92c, 94c and the connected ones of the intake valves 22 and / or exhaust valves 24.

[0036] 9-11, the first valve lift switch 150 is housed within a bore 152 extending within the output rocker lever 102 and therefrom to the first input rocker lever 104. The first switch 150 includes a first valve lift pin assembly 154 including a spring biased first valve lift pin 156 having a plurality of shear pin portions 170, 172, 174 in abutting end-to-end engagement. As shown in FIG. 9, the first valve lift pin 156 is normally biased to an engaged position via springs 158a, 158b such that the first input rocker lever 104 is connected to the output rocker lever 102. In the engaged position, the valve lift pin 156 spans joints 160, 162 between the rocker levers 102, 104, forming shear interfaces 160a, 162a at the joints 160, 162. The engaged position of the first valve lift switch 150 is used during operating conditions when standard or nominal lift of the intake valve 22 or exhaust valve 24 is desired from the camshaft lobes 92a, 94a.

[0037] To disconnect or decouple the rocker levers 102, 104 from one another, hydraulic fluid pressure is provided from the rocker shaft 120 of the engine 12 through the hydraulic system of the engine 12 into the bore 152 through the opening 166 and into the space 164 at one end of the bore 152. As shown in Figures 10 and 11, the hydraulic pressure displaces the valve lift pin 156 into contact with the base 168, compressing the springs 158a, 158b. In this state, the junction between the shear pin portions 170 and 172 is aligned with the joint 160, and the junction between the shear pin portions 172 and 174 is aligned with the joint 162. This disengaged position eliminates the shear interfaces 160a, 162a as no portion of the first valve lift pin 156 spans the joints 160, 162. As a result, rotation of the first input rocker lever 104 is not transmitted to the output rocker lever 102 and motion imparted by the camshaft lobes 92a, 94a is not transmitted to the intake valves 22 or exhaust valves 24 but rather is absorbed by the biasing spring 124. The disengaged position of the first valve lift switch 150 is used during operating conditions where cylinder deactivation is desired and / or alternating lift profiles from the second input rocker 106 and third input rocker 108 from the camshaft lobes 92b, 94b, 92c, 94c are desired.

[0038] The second valve lift switch 200 is received in a bore 202 that extends within the output rocker lever 102 and from there to the second input rocker lever 106 and the third input rocker lever 108. The second valve lift switch 200 includes a second valve lift pin assembly 204 that includes a second valve lift pin 206 with a plurality of shear pin portions 220, 222 in abutting end-to-end engagement. As shown in Figures 9 and 10, the second valve lift pin 206 is normally biased to a disengaged position via a spring 208.

[0039] In the engaged position shown in Figure 11, the second input rocker lever 106 and the third input rocker lever 108 are connected to the output rocker lever 102. In the engaged position, the valve lift pin 206 spans joints 210, 212 between the rocker levers 102, 106, 108, forming shear interfaces 210a, 212a at the joints 210, 212. The engaged position of the second valve lift switch 200 is used during operating conditions where alternating lift of the intake valves 22 or exhaust valves 24 is required from the camshaft lobes 92b, 94b, 92c, 94c via the input rocker levers 106, 108. To connect or couple the rocker levers 102, 106, 108 to one another, hydraulic fluid pressure is supplied from the rocker shaft 120 of the engine 12, through an opening 216, into the bore 202, and into a control pressure space 214 at one end of the bore 202, via the hydraulic system of the engine 12. As shown in FIG. 11, hydraulic fluid pressure displaces the valve lift pin 206 into contact with the base 218 , compressing the spring 208 .

[0040] 9 and 10, the interface between the shear pin portions 220 and 222 is aligned with the joint 210 and the end of the shear pin portion 222 is positioned within the output rocker lever 102 such that the shear pin portion 222 does not span the joint 212. This disengaged position eliminates the shear interface 210a, 212a as no portion of the second valve lift pin 206 spans the joints 210, 212. As a result, rotation of the second input rocker lever 106 and the third input rocker lever 108 is not transmitted to the output rocker lever 102 and motion imparted by the camshaft lobes 92b, 94b, 92c, 94c is not transmitted to the intake valves 22 or exhaust valves 24 but rather is absorbed by the biasing springs 126, 128. The disengaged position of the second valve lift switch 200 is used during operating conditions where cylinder deactivation is desired or while a nominal or standard lift profile from the first input rocker 104 is desired from the camshaft lobes 92a, 94a.

[0041] 12-18 illustrate another embodiment locker system 300. Locker system 300 may be similar to locker system 100 discussed above, and the following discussion is directed to additional features of locker system 300. One or more aspects or features of locker system 100 discussed above may be provided in locker system 300, and vice versa.

[0042] 12-13, the rocker system 300 includes an output rocker lever 302, a first input rocker lever 304, a second input rocker lever 306, and a third input rocker lever 308, each rotatably mountable to an engine component 120, such as a rocker shaft. The first input rocker lever 304 includes a first roller 310 for direct or indirect contact with a corresponding camshaft lobe 92a, 94a. The second input rocker lever 306 includes a second roller 312 for direct or indirect contact with a corresponding camshaft lobe 92b, 94b. The third input rocker lever 308 includes a third roller 314 for direct or indirect contact with a corresponding camshaft lobe 92c, 94c.

[0043] One or more of the input rocker levers 304, 306, 308 are selectively connectable to the output rocker lever 302 to transfer motion from the respective camshaft lobes 92a, 94a, 92b, 94b, 92c, 94c to the connected ones of the intake valves 22 or exhaust valves 24. Additionally, the input rocker levers 304, 306, 308 can be disconnected from the output rocker lever 302 such that no valve lift is provided during cylinder deactivation. Connection and disconnection between the output rocker 302 and the input rockers 304, 306, and / or 308 can be effected by engagement of the output rocker 302 to the input rockers 304, 306, and / or 308, by engagement of the input rockers 304, 306, and / or 308 to the output rocker 302, and combinations thereof.

[0044] The biasing mechanism 322 includes springs 324, 326, 328, each of which contacts the output rocker lever 302 and a respective one of the input rocker levers 304, 306, 308 to bias the corresponding roller 310, 312, 314 into direct or indirect contact with a respective camshaft lobe. The biasing mechanism 322 differs from the biasing mechanism 122 in that the spring 324 of the first input rocker lever 304 is provided on the same side of the rocker assembly as the lash adjusters 330, 332. The lash adjusters 330, 332, which may be mechanical or hydraulic, are connected to the respective arms 302a, 302b of the output rocker lever 302 and the corresponding one of the intake valves 22 or exhaust valves 24.

[0045] The rocker system 300 includes a first valve lift switch 350 that selectively connects and disconnects the first input rocker lever 304 and the output rocker lever 302 to transfer or prevent the transfer of motion between the associated camshaft lobes 92a, 94a and the connected ones of the intake valves 22 and / or exhaust valves 24. The rocker system 300 also includes a second valve lift switch 400 that selectively connects and disconnects one or both of the second input rocker lever 306 and the third input rocker lever 308 and the output rocker lever 302 to transfer or prevent the transfer of motion between the associated camshaft lobes 92b, 94b, 92c, 94c and the connected ones of the intake valves 22 and / or exhaust valves 24.

[0046] 14-16, the first valve lift switch 350 is housed within a bore 352 that extends within the output rocker lever 302 and therefrom to the first input rocker lever 304. As shown in FIG. 14, the first valve lift switch 350 includes a first valve lift pin assembly 354 that includes a first valve lift pin 356 with a plurality of shear pin portions 370, 372 that are normally biased away from each other to an engaged position via a spring 358 such that the first input rocker lever 304 is normally connected to the output rocker lever 302. In the engaged position, the valve lift pin 356 spans joints 360, 362 between the rocker levers 302, 304, forming shear interfaces 360a, 362a at the joints 360, 362. The engaged position of the first switch 350 is used during operating conditions when a reference or nominal lift of the intake valve 22 or exhaust valve 24 is desired from the camshaft lobes 92a, 94a.

[0047] To disconnect or decouple the rocker levers 302, 304 from one another, hydraulic fluid pressure is provided from the rocker shaft 120 of the engine 12 through the hydraulic system of the engine 12, through the openings 366a, 366b into the bore 352 and into the spaces 364a, 364b at the opposite ends of the bore 352. As shown in Figures 15 and 16, the hydraulic fluid pressure displaces the shear pin portions 370, 372 toward one another by compressing the spring 358. In this condition, the entire shear pin portions 370, 372 are moved into the first input rocker lever 304. This disengaged position eliminates the shear interface 360a, 362a as no portion of the first valve lift pin 356 spans the joints 360, 362. As a result, rotation of the first input rocker lever 304 is not transmitted to the output rocker lever 302 and motion imparted by the camshaft lobes 92a, 94a is not transmitted to the intake valves 22 or the exhaust valves 24. The disengaged position of the first valve lift switch 350 is used during operating conditions where cylinder deactivation is desired or while alternating lift profiles from the second and third input rockers 306, 308 are desired from the camshaft lobes 92b, 94b, 92c, 94c.

[0048] The second valve lift switch 400 is received within a bore 402 of the output rocker lever 302, the second input rocker lever 306, and the third input rocker lever 308. The second valve lift switch 400 includes a second valve lift pin assembly 404 that includes a bore 402 containing a second valve lift pin 406 with a plurality of shear pin portions 420, 422. As shown in Figures 14 and 15, the shear pin portions 420, 422 are normally biased within the bore 402 towards each other via springs 408, 409 and against a central base 418 to a disengaged position.

[0049] 16, the second input rocker lever 306 and the third input rocker lever 308 are connected to the output rocker lever 302. In the engaged position, the shear pin portions 420, 422 of the shear pin 406 span joints 410, 412 between the rocker levers 302, 306, 308 forming shear interfaces 410a, 412a at the joints 410, 412. The engaged position of the second valve lift switch 400 is used during which alternating lift of the intake valves 22 or exhaust valves 24 is desired from the camshaft lobes 92b, 94b, 92c, 94c via the input rocker levers 306, 308. To connect or couple the rocker levers 302, 306, 308 to one another, hydraulic fluid pressure is supplied from the rocker shaft 120 of the engine 12, via the hydraulic system of the engine 12, through the opening 416 into the bore 402 and into the control pressure space 414 of the bore 402 between the shear pin portions 420, 422. As shown in FIG. 16 , the hydraulic fluid pressure displaces the shear pin portions 420, 422 from the base 418 and compresses the springs 408, 409 such that the shear pin portions span the joints 410, 412.

[0050] In the disengaged state, the shear pin portions 420, 422 are positioned within the output rocker lever 302 such that the shear pin portions 420, 422 do not span the joints 410, 412. This disengaged position eliminates the shear interface 410a, 412a as no portion of the second valve lift pin 406 spans the joints 410, 412. As a result, rotation of the second input rocker lever 306 and the third input rocker lever 308 is not transferred to the output rocker lever 302 and motion imparted by the camshaft lobes 92b, 94b, 92c, 94c is not transferred to the intake valves 22 or the exhaust valves 24. The disengaged position of the second valve lift switch 400 is used during operating conditions where cylinder deactivation is desired or while a nominal or standard lift profile from the first input rocker lever 304 is desired from the camshaft lobes 92a, 94a.

[0051] 17-18 illustrate an exemplary assembly process for assembling the output rocker lever 302 and the first input rocker lever 304. In FIG. 17, the shear pin portions 370, 372 may be held in place via temporary assembly pins 450, 452 inserted into assembly holes 454, 456, respectively, of the output rocker lever 302. The assembly pins 450, 452 hold the shear pin portions 370, 372 in the retracted position of the output rocker lever 302 with a spring 358 compressed therebetween. Once the input rocker lever 304 is aligned with the output rocker lever 302, the assembly pins 450, 452 may be removed, allowing the shear pin portions 370, 372 to be flipped into place and span the joints 410, 412 to complete the assembly. Each shear pin portion 370, 372 may be provided with a slot 458, 460, respectively, to receive a screwdriver or other tool to assist in aligning the respective shear pin portion 370, 372 to receive the corresponding assembly pin 450, 452.

[0052] 19-24 illustrate another embodiment locker system 500. Locker system 500 may be similar to locker systems 100, 300 discussed above, and the following discussion is directed to additional features of locker system 500. One or more aspects or features of locker systems 100, 300 discussed above may be provided in locker system 500, and vice versa.

[0053] 19, the rocker system 500 includes an output rocker lever 502, a first input rocker lever 504, a second input rocker lever 506, and a third input rocker lever 508, each rotatably mountable to an engine component 120, such as a rocker shaft. The first input rocker lever 504 includes a first roller 510 for direct or indirect contact with a corresponding camshaft lobe 92a, 94a. The second input rocker lever 506 includes a second roller 512 for direct or indirect contact with a corresponding camshaft lobe 92b, 94b. The third input rocker lever 508 includes a third roller 514 for direct or indirect contact with a corresponding camshaft lobe 92c, 94c.

[0054] One or more of the input rocker levers 504, 506, 508 are controlled to selectively connect with the output rocker lever 502 to transfer motion from the respective camshaft lobes 92a, 94a, 92b, 94b, 92c, 94c to the connected ones of the intake valves 22 or exhaust valves 24. Additionally, the input rocker levers 504, 506, 508 can be controlled to selectively disconnect from the output rocker lever 502 such that no valve lift is provided during cylinder deactivation. The controlled connection and disconnection of the output rocker 502 to the input rockers 504, 506, and / or 508 can be effected by engagement of the output rocker 502 to the input rockers 504, 506, and / or 508, by engagement of the input rockers 504, 506, and / or 508 to the output rocker 502, and combinations thereof.

[0055] The biasing mechanism includes brake biasing springs 524, 526, each in contact with the input rocker lever 506, 508 and the output rocker lever 502, respectively, and a standard biasing spring 522 in contact with the input rocker lever 504 and the output rocker lever 502 to bias the corresponding rollers 510, 512, 514 into direct or indirect contact with the respective camshaft lobes. Lash adjusters 530, 532, which may be mechanical or hydraulic, are connected to the output rocker lever 502 and the corresponding one of the intake valve 22 or exhaust valve 24.

[0056] The rocker system 500 includes a first valve lift switch 550 that selectively connects and disconnects the first input rocker lever 504 and the output rocker lever 502 to transfer or prevent the transfer of motion between the associated camshaft lobes 92a, 94a and the connected ones of the intake valves 22 and / or exhaust valves 24. The rocker system 500 also includes a second valve lift switch 600 that selectively connects and disconnects the input rocker levers 506, 508 and the output rocker lever 502 to transfer or prevent the transfer of motion between the associated camshaft lobes 92b, 94b, 92c, 94c and the connected ones of the intake valves 22 and / or exhaust valves 24.

[0057] 20-22, the first valve lift switch 550 is housed within a bore 552 extending between the output rocker lever 502 and the first input rocker lever 504. As shown in FIG. 20, the first valve lift switch 550 includes a first valve lift pin assembly 554 including a first valve lift pin 556 with a plurality of shear pin portions 570, 572, 574 that are normally biased into an engaged position against an end base 518 into contact with one another via a spring 558 such that the first input rocker lever 504 is normally connected to the output rocker lever 502. In the engaged position, the valve lift pin 556 spans joints 560, 562 between the rocker levers 502 and 504, forming shear interfaces 560a, 562a at the joints 560, 562. The engaged position of the first switch 550 is used during operating conditions when a reference or nominal lift of the intake valve 22 or exhaust valve 24 is desired from the camshaft lobes 92a, 94a.

[0058] To disconnect or decouple the rocker levers 502, 504 from one another, hydraulic fluid pressure is provided from the rocker shaft 120 of the engine 12, through the hydraulic system of the engine 12, into the bore 552 and into a control volume 566 at the end of the bore 552 opposite the spring 558. As shown in Figures 21 and 22, the hydraulic fluid pressure in the control volume 566 displaces the shear pin portions 570, 572, 574 from the end base 518 toward the opposite end of the bore 552, compressing the spring 558. In this condition, the joints between the ends of the shear pin portions 570, 572, 574 are moved into alignment with the joints 560, 562. This aligned position eliminates the shear interfaces 560a, 562a as no portion of the first valve lift pin 556 spans the joints 560, 562. As a result, rotation of the first input rocker lever 504 is not transmitted to the output rocker lever 502 and motion imparted by camshaft lobes 92a, 94a is not transmitted to the intake valves 22 or exhaust valves 24. The disengaged position of the first valve lift switch 550 is used during operating conditions where cylinder deactivation is desired or while alternating lift profiles from the second input rocker 506 and third input rocker 508 are desired from camshaft lobes 92b, 94b, 92c, 94c.

[0059] The second valve lift switch 600 is received within bores 602 of the output rocker lever 502, the second input rocker lever 506, and the third input rocker lever 508. The second valve lift switch 600 includes a second valve lift pin assembly 604 including a second valve lift pin 606 with a plurality of shear pin portions 620, 622, 624 within the bore 602. As shown in Figures 20 and 21, the shear pin portions 620, 622, 624 are normally biased within the bore 602 via a spring 608 into end-to-end contact and into a disengaged position against an end base 618.

[0060] 22, the second input rocker lever 506 and the third input rocker lever 508 are connected to the output rocker lever 502. In the engaged position, the shear pin portions 620, 622, 624 of the shear pin 606 span joints 610, 612 between the rocker levers 502, 506, 508 forming shear interfaces 610a, 612a at the joints 610, 612. The engaged position of the second valve lift switch 600 is used during operating conditions when alternating lift of the intake valves 22 or exhaust valves 24 is desired from the camshaft lobes 92b, 94b, 92c, 94c via the input rocker levers 506, 508. To connect or couple the rocker levers 502, 506, 508 to one another, hydraulic fluid pressure is provided from the rocker shaft 120 of the engine 12, via the hydraulic system of the engine 12, through the opening 616 into the bore 602 and into the control pressure space 614 of the bore 602 in the end base 618. As shown in FIG. 22, the hydraulic fluid pressure displaces the shear pin portions 620, 622, 624 from the end base 618 and compresses the spring 608 so that the shear pin portions span the joints 610, 612.

[0061] In the disengaged state, the shear pin portions 620, 622, 624 are positioned within the output rocker lever 502 and the input rocker lever 506, 508 such that the shear pin portions 620, 622, 624 do not span the joints 610, 612. This disengaged position eliminates the shear interfaces 610a, 612a because no portion of the second valve lift pin 606 spans the joints 610, 612. As a result, rotation of the second input rocker lever 506 and the third input rocker lever 508 is not transferred to the output rocker lever 502 and motion imparted by the camshaft lobes 92b, 94b, 92c, 94c is not transferred to the intake valves 22 or the exhaust valves 24. The disengaged position of the second valve lift switch 600 is used during operating conditions where cylinder deactivation is desired or while a nominal or standard lift profile from the first input rocker lever 504 is desired from the camshaft lobes 92a, 94a.

[0062] 23-24, the rocker system 500 shows a plurality of stop pins 580 engaged with each of the input rocker levers 504, 506, 508. The output rocker lever 502 includes a stop member protrusion 582 that contacts the stop member 580 when a portion of the holes 552, 602 are aligned with one another. The stop pin 580 is configured to prevent the output rocker lever 502 from rotating too far in the clockwise direction of FIG. 23. The stop pin 580 also prevents the input rocker levers 504, 506, 508 from rotating too far in the counterclockwise direction. This ensures that the portions of the holes 552 and / or holes 602 that accommodate various portions of the valve lift pins 556, 606 are aligned with one another along the base circles of the respective cam lobes, even when the lash adjustment of the intake valves 22 and / or exhaust valves 24 is changed. The aligned portions of the holes 552 , 602 allow the valve lift pins 556 , 606 to smoothly actuate to selectively engage the input rockers 504 , 506 , 508 and the output rocker 502 .

[0063] 25-28, there is shown another embodiment of a rocker system 700. The rocker system 700 may be similar to the rocker systems 100, 300, 500 discussed above, and the following discussion is directed to additional features of the rocker system 700. One or more aspects or features of the rocker systems 100, 300, 500 discussed above may be provided in the rocker system 700, and vice versa.

[0064] 25-27, a rocker system 700 includes a first output rocker lever 702, a second output rocker lever 704, and a first input rocker lever 706, each rotatably mountable to an engine component 120, such as a rocker shaft. A retaining ring 121 may be provided to secure the rocker levers 702, 704, 706 on the rocker shaft 120. The second output rocker lever 704 includes a first roller 710 for direct or indirect contact with a corresponding camshaft lobe 92a, 94a. The first input rocker lever 706 includes a second roller 712 for direct or indirect contact with a corresponding camshaft lobe 92b, 94b. If desired, one or more additional input rocker levers may be provided for direct or indirect contact with other camshaft lobes if additional valve lift functionality is required.

[0065] The second output rocker lever 704 is controllable to selectively connect with the first output rocker lever 702 to transfer motion from the respective camshaft lobes 92a, 94a to the connected ones of the intake valves 22 or exhaust valves 24. Additionally, the second output rocker lever 704 and / or the input rocker lever 706 can be controlled to connect and disconnect with each other relative to the first output rocker lever 702 such that alternating valve lift can be provided from the input rocker lever 706 to the second output rocker lever 704. Connection and disconnection between the output rocker levers 702, 704 and the input rocker lever 706 can be effected by engagement of the first output rocker lever 702 with the rocker levers 704, 706, by engagement of the second output rocker lever 704 with the first output rocker lever 702 and the input rocker lever 706, by engagement of the input rocker lever 706 with the second output rocker lever 704, and combinations thereof.

[0066] The biasing mechanism includes biasing springs 724, 726 that each contact the output rocker lever 702 and each of the output rocker levers 704 and input rocker levers 706 to bias the corresponding rollers 710, 712 into direct or indirect contact with the respective camshaft lobes. Lash adjusters 730, 732, which may be mechanical or hydraulic, are connected to the output rocker levers 702, 704 and the corresponding ones of the intake valves 22 or exhaust valves 24.

[0067] The rocker system 700 includes a valve lift switch 750 that is controllable to selectively connect and disconnect a first output rocker lever 702 and a second output rocker input rocker lever 704 and simultaneously connect a second output rocker lever 704 and an input rocker lever 706 to transmit or prevent motion between an associated camshaft lobe and a connected one of the intake valves 22 and / or exhaust valves 24. The rocker system 700 may also include additional valve lift switches, such as those disclosed herein, that are controlled to selectively connect and disconnect additional input rocker levers for additional functions, such as cylinder deactivation, two-stroke braking, etc.

[0068] 28, the valve lift switch 750 is housed within a bore 752 extending within and from the first output rocker lever 702, the second output rocker lever 704, and the input rocker lever 706. As shown in FIG. 28, the valve lift switch 750 includes a first valve lift pin assembly 754 including a first valve lift pin 756 with a plurality of shear pin portions 770, 772 biased by springs 758, 759 to normally connect to the first output rocker lever 702 and the second output rocker lever 704 and to disconnect the input rocker lever 706. In the engaged position, the valve lift pin 756 spans a joint 760 between the rocker levers 702, 704 forming a shear interface 760a at the joint 760. The engaged position of switch 750 is used during operating conditions when a reference or nominal lift of the intake valve 22 or exhaust valve 24 is desired from the camshaft lobes 92a, 94a.

[0069] To disconnect or decouple the output rocker levers 702, 704 from one another, hydraulic fluid pressure is provided from the rocker shaft 120 of the engine 12, through the hydraulic system of the engine 12, into the bore 752 and into the control volume 766 at the end of the bore 752 opposite the springs 758, 759. The hydraulic fluid pressure in the control volume 766 displaces the shear pin portions 770, 772 toward the opposite end of the bore 752, compressing the springs 758, 759. In this condition, the shear pin portion 770 moves away from the first input rocker lever 702 and aligns with the joint 760. This aligned position eliminates the shear interface 760a, as no portion of the first valve lift pin 756 spans the joint 760. As a result, rotation of the second output rocker lever 704 is not transmitted to the first output rocker lever 702 and motion imparted by the camshaft lobes 92a, 94a is not transmitted to the intake valves 22 or exhaust valves 24.

[0070] Actuation of the valve lift switch 750 also simultaneously connects the input rocker lever 706 and the second output rocker lever 704. Displacement of the shear pin portion 770 displaces the shear pin portion 772, which spans joint 762 and joint 764, creating a shear interface between the rocker levers 704 and 706 at joints 762, 764. This actuated position of the valve lift switch 750 is used during operating conditions in which braking or other alternating valve lift is required for the valves and alternating camshaft lobes 92b, 94b, 92c, 94c connected to the second output rocker 704 via the input rocker lever 706. Other embodiments contemplate the use of other input rockers and / or valve lift switches to connect other input rockers and / or provide cylinder deactivation.

[0071] 29-30, there is shown another embodiment of a rocker system 800. The rocker system 800 may be similar to the rocker systems 100, 300, 500, 700 discussed above, and the following discussion is directed to additional features of the rocker system 800. One or more aspects or features of the rocker systems 100, 300, 500, 700 discussed above may be provided in the rocker system 800, and vice versa.

[0072] The rocker system 800 includes a first output rocker lever 802, a second output rocker lever 804, a first input rocker lever 806, and a second input rocker lever 808, each rotatably mountable to an engine component 120, such as a rocker shaft. The first input rocker lever 806 includes a first roller 810 for direct or indirect contact with a corresponding camshaft lobe 92a, 94a. The second input rocker lever 808 includes a second roller 812 for direct or indirect contact with a corresponding camshaft lobe 92b, 94b. If desired, one or more additional input rocker levers can be provided for direct or indirect contact with other camshaft lobes if additional valve function is required.

[0073] The first input rocker lever 806 is selectively connectable with the first output rocker lever 802 and the second output rocker lever 804 to transfer motion from the respective camshaft lobes 92a, 94a to the connected ones of the intake valves 22 or exhaust valves 24. Additionally, the second input rocker lever 808 can be connected to the second output rocker lever 804 to provide alternating valve lift from the second input rocker lever 808 to the second output rocker lever 804. Connection and disconnection of the output rocker levers 802, 804 and the input rocker levers 806, 808 can be effected by engagement of the output rocker lever to the input rocker lever, by engagement of the input rocker lever to the output rocker lever, and combinations thereof.

[0074] The biasing mechanism includes biasing springs 824, 826, 828 that each contact the output rocker levers 802, 804 and input rocker levers 806, 808, respectively, to bias the corresponding rollers 810, 812 into direct or indirect contact with the respective camshaft lobes. Lash adjusters 830, 832, which may be mechanical or hydraulic, are connected to the output rocker levers 802, 804 and the corresponding ones of the intake valves 22 or exhaust valves 24.

[0075] The rocker system 800 includes a first valve lift switch 850 that can be controlled to selectively connect and disconnect a first output rocker lever 802 and a second output rocker input rocker lever 804 to a first input rocker lever 806. Similar to the valve lift switches discussed above, the first valve lift switch 850 includes a valve lift pin assembly 854 that includes a valve lift pin 856 with a plurality of shear pin portions 858, 860, 862. In the engaged position, the shear pin portions 860, 862 span shear interfaces 864a, 866a at joints 864, 866, connecting the first input rocker lever 806 to the output rocker levers 802, 804. The valve lift pin 856 can be hydraulically actuated to compress the springs 852, 853 and align the shear pin portions 858, 860, 862 and joints 864, 866 in end-to-end abutment to decouple the first input rocker lever 806 from the output rocker levers 802, 804, for example for cylinder deactivation.

[0076] The rocker system 800 includes a second valve lift switch 870 for selectively connecting the second input rocker lever 808 to the second output rocker lever 804 to provide alternating valve lift profiles from different cam lobes. The second valve lift switch 870 includes a valve lift pin assembly 874 including a first pin portion 876 and a second pin portion 878 normally biased into the second input rocker lever 808 by springs 880, 882. Hydraulic fluid pressure is used to actuate the first pin portion 876 and the second pin portion 878 away from each other to bridge the joints 884, 886 between the second input rocker lever 808 and the second output rocker lever 804. The second input rocker lever 808 can be connected to the second output rocker lever 804, for example, during exhaust braking.

[0077] 31-32, several exhaust rocker systems 900a, 900b (collectively and individually referred to as exhaust rocker systems 900) and intake rocker systems 990a, 990b (collectively and individually referred to as intake rocker systems 990) are shown along two cylinders 14 of an engine. The intake rocker system 990 includes a pair of output rocker levers 992 each connected to an intake valve with a crosshead 998. The intake rocker system 990 also includes two input rocker levers 994, 996 that are selectively connected and disconnected from the respective output rocker levers 992 to provide a desired intake valve lift profile.

[0078] Each exhaust rocker system 900 includes an output rocker lever 902 connected to a single exhaust valve 24 for each cylinder 14. The exhaust rocker system 900 also includes a first input rocker lever 904 and a second input rocker lever 906 that are selectively connected and disconnected from the output rocker lever 902 to provide the desired valve lift.

[0079] 32, a first valve lift switch 920 is provided for selectively connecting and disconnecting an output rocker lever 902 and a first input rocker lever 904. Similar to the valve lift switches discussed above, the first valve lift switch 920 includes a valve lift pin assembly 924 including a valve lift pin 926 with a plurality of shear pin portions 928, 930. In a normally engaged position, the valve lift pin 926 is biased by a spring 932 such that the shear pin portion 928 spans a joint 934 and connects the first input rocker lever 904 to the output rocker lever 902. The valve lift pin 926 can be hydraulically actuated to compress the spring 932 and align the shear pin portions 928, 930 in end-to-end abutment with the joint 934 to decouple the first input rocker lever 904 from the output rocker lever 902, for example, for cylinder deactivation.

[0080] The exhaust rocker system 900 includes a second valve lift switch 940 for selectively connecting the second input rocker lever 906 to the output rocker lever 902 to provide alternating valve lift profiles from different cam lobes. The second valve lift switch 940 includes a valve lift pin assembly 944 including a first pin portion 946 and a second pin portion 948 normally biased by a spring 952 to align the pin portions 946, 948 and a joint 954 in end-to-end abutment. Hydraulic fluid pressure is used to actuate the first pin portion 946 and the second pin portion 948 to compress the spring 952 to span the joint 954 with the first pin portion 946 between the second input rocker lever 906 and the output rocker lever 902. The second input rocker lever 906 can be connected to the output rocker lever 902, for example during exhaust braking.

[0081] 33, another embodiment of a rocker system 1000 is shown. The rocker system 1000 includes a first output rocker lever 1002 and a second output rocker lever 1004, such as a rocker shaft, each rotatable about the engine component 120. Any suitable engine component about which the rocker levers can rotate is contemplated. The first output rocker lever 1002 and the second output rocker lever 1004 each include a mechanical lash adjuster 1006, 1008. In another embodiment, the lash adjusters 1006, 1008 are hydraulic lash adjusters rather than mechanical lash adjusters. The rocker system 1000 also includes an input rocker lever 1010, which is rotatable about the engine component 120. The input rocker lever 1010 is operatively associated with the first output rocker lever 1002 and the second output rocker lever 1004 and operates in two modes to impart a lift profile to the first output rocker lever 1002 and the second output rocker lever 1004. As used herein, a lift profile may also include a partial lift profile.

[0082] In the first mode, the input rocker lever 1010 operates in either an actuated or at rest state. In the actuated state, the input rocker lever 1010 engages the first output rocker lever 1002 and the second output rocker lever 1004 to cause rotational movement of the first output rocker lever 1002 and the second output rocker lever 1004 by the cam lobe acting on the roller 1020. Alternatively, the first output rocker lever 1002 and the second output rocker lever 1004 engage the input rocker lever 1010. In the at rest state, the input rocker lever 1010 is disengaged from the first output rocker lever 1002 and the second output rocker lever 1004 to absorb the movement of the cam lobe 1020 through the lost motion devices 1012, 1014. The lost motion devices 1012, 1014 may include, for example, a compressible body capable of exerting a reaction force, a coil spring, a spiral spring, a wave spring, or a hydraulic cylinder. In the first mode, at rest, valve motion of the connected intake valves 22 and exhaust valves 24 may be blocked.

[0083] In the second mode, the input rocker lever 1010 operates in either an actuated state or a rest state. In the actuated state, the input rocker lever 1010 engages either the first output rocker lever 1002 or the second output rocker lever 1004 to cause rotational movement of the associated engaged rocker lever 1002, 1003. Alternatively, one of the first output rocker lever 1002 or the second output rocker lever 1004 engages the input rocker lever 1010. The non-associated output rocker lever 1002, 1004 is disengaged and absorbs cam lobe movement through the corresponding lost motion device 1012, 1014. In the rest state, the input rocker lever 1010 is disengaged from the first output rocker lever 1002 and the second output rocker lever 1004 to absorb cam lobe movement through the lost motion device 1012, 1014. In the second mode, a pause state, valve movement of the connected intake valves 22 and / or exhaust valves 24 may be blocked.

[0084] Referring to FIG. 34, another embodiment of a rocker system 1100 is shown. The rocker system 1100 includes a single output rocker lever 1102 rotatable about the engine component 120. The output rocker lever 1102 is configured to impart motion to the two intake valves 22 or the two exhaust valves 24 and is configured with mechanical lash adjusters 1106, 1108. In another embodiment, the lash adjusters 1106, 1108 are hydraulic lash adjusters rather than mechanical lash adjusters. The rocker system 1100 also includes an input rocker lever 1110 rotatable about the engine component 120. The input rocker lever 1110 imparts a lift profile to the output rocker lever 1102 via a roller 1120 that receives motion from a cam lobe.

[0085] The input rocker lever 1110 can be operated in an actuated or at rest state. In the actuated state, the input rocker lever 1110 engages the output lever 1102 to cause rotational movement of the output rocker lever 1102. Alternatively, the output rocker lever 1102 engages the input rocker lever 1110. In the at rest state, the input rocker lever 1110 is disengaged from the output rocker lever 1102 to absorb cam lobe motion through a lost motion device 1112.

[0086] 35, there is shown another embodiment rocker system 1200. Rocker system 1200 is similar to rocker system 1000, with like components being indicated with like reference numbers. However, rocker system 1200 includes a second input rocker lever 1202 that is rotatable about engine component 120 in response to motion imparted to a cam roller 1206 by a second cam lobe.

[0087] The second input rocker lever 1202 operates in two modes. In the first mode, the first input rocker lever 1010 is selectively engageable with both the output rocker levers 1002, 1004. In the actuated state of the second input rocker lever 1202 in the first mode, the second input rocker lever 1202 and the associated output rocker lever 1002 engage with each other while the first input rocker lever 1010 is at rest to cause rotational movement of the associated output rocker lever 1002 with only the second input rocker lever 1202. In the at rest state of the second input rocker lever 1202, the second input rocker lever 1202 is disengaged from the associated output rocker lever 1002 to absorb the movement of the cam lobes through the lost motion device 1204. Thus, in the first mode, the second input rocker lever 1202 can be counteracted / pulled by the first input lever 1010 for engagement with both of the output rocker levers 1002, 1004. Also, in the first mode of the second input rocker lever 1202, the second input rocker lever 1202 can be counteracted / pulled by the first input rocker lever 1010 or can be counteracted / pulled by the first input rocker lever 1010 from a corresponding one of the output rocker levers 1002, 1004.

[0088] In the second mode of the second input rocker lever 1202, the first input rocker lever 1010 is controlled to be selectively engageable with only one of the output rocker levers 1002, 1004. In the actuated state of the second input rocker lever 1202 in the second mode, the second input rocker lever 1202 engages the associated output rocker lever 1002 to cause rotational movement of the associated output rocker lever 1002. In the rested state of the second input rocker lever 1202, the second input lever 1202 is disengaged from the associated output rocker lever 1002 to absorb cam lobe movement through the lost motion device 1204. In the second mode of the second input rocker lever 1202, the second input rocker lever 1202 can be actuated simultaneously with the first input lever 1010 to engage different ones of the input rocker levers 1002, 1004. Also, in the second mode of the second input rocker lever 1202, the second input rocker lever 1202 and the first input rocker lever 1010 can be paused simultaneously or inversely with respect to each other.

[0089] In the actuation states of the second input rocker lever 1202 in the first and second modes, the second input rocker lever 1202 can impart at least one of a normal lift event, a brake lift event, a late intake valve closing (LIVC), an early intake valve closing (EIVC), a late intake valve opening (LIVO), an early intake valve opening (EIVO), an early exhaust valve opening (EEVO), an early exhaust valve closing (EEVC), a late exhaust valve closing (LEVC), a late exhaust valve opening (LEVO), an internal exhaust gas recirculation (i-EGR) lift event, a lift increase, a lift decrease, an early extended dwell, or a late extended dwell to the second valve 22, 24, independent of the first valve 22, 24.

[0090] 36, another embodiment rocker system 1300 is shown. The rocker system 1300 includes a combined input / output rocker lever 1302 rotatable about the engine component 120. The combined input / output rocker lever 1302 includes a lash adjuster 1306. The rocker lever assembly 1300 also includes a second output rocker lever 1304 rotatable about the engine component 120, the second output rocker lever 1304 including a lash adjuster 1308.

[0091] A combined input / output rocker lever 1302 in operative association with a second output rocker lever 1304 imparts a fixed lift profile to the first valve and selectively imparts the same lift profile to the second output rocker lever 1304. The second output rocker lever 1304 operates in association with the combined input / output rocker lever 1302 in an actuated or idle state. In the actuated state, the combined input / output rocker lever 1302 and the second output rocker lever 1304 are engaged to cause rotational movement of the second output rocker lever 1304. In the idle state, the combined input / output rocker lever 1302 and the second output rocker lever 1304 are disengaged to absorb cam lobe movement through a lost motion device 1312.

[0092] A second input rocker lever 1310 operatively associated with the second output rocker lever 1304 can impart a lift profile to the second output rocker lever 1304. The second input rocker lever 1310 operates in an opposite actuated / rested state relative to the combined input / output rocker lever 1302 and can even be rested simultaneously with the combined input / output rocker lever 1302.

[0093] In an actuated state of the second input rocker lever 1310, the second input rocker lever 1310 engages the second output rocker lever 1304 to cause rotational movement of the second output rocker lever 1304. In a rested state, the second input rocker lever 1310 disengages from the second output rocker lever 1304 to absorb cam lobe movement through a lost motion device 1314. In an actuated state, the second input rocker lever 1310 can impart at least one of a normal lift event, a brake lift event, a LIVC, EIVC, LIVO, EIVO, EEVO, EEVC, LEVC, LEVO, i-EGR lift event, lift reduction, lift increase, an early extension dwell, or a late extension dwell to the second valve, independent of the first valve.

[0094] 37, a rocker system 1400 is shown that is similar to the rocker system 1100 and also includes a single output rocker lever 1402 rotatable about the engine component 120. The output rocker lever 1402 is configured to impart motion to the two intake valves 22 or the two exhaust valves 24 and is configured with lash adjusters 1406, 1408. The rocker system 1400 also includes a first input rocker lever 1410 and a second input rocker lever 1412, each rotatable about the engine component 120. Lost motion devices 1414, 1416 are associated with each of the first input rocker lever 1410 and the second input rocker lever 1412.

[0095] Each of the first input rocker lever 1410 and the second input rocker lever 1412 is operatively associated with the output rocker lever 1402 to impart a lift profile to the output rocker lever 1402. The second input rocker lever 1412 operates in either an inverse actuated state relative to the first input rocker lever 1410, and a simultaneous or inverse rest state with the first input rocker lever 1410. In an actuated state, the second input rocker lever 1412 engages the output rocker lever 1402 to cause rotational movement of the output rocker lever 1402.

[0096] In a rest state, the second input rocker lever 1412 is disengaged from the output rocker lever 1402 to absorb cam lobe motion through a lost motion device 1416. In an actuated state, the second input rocker lever 1412 can impart at least one of a normal lift event, a brake lift event, a LIVC, EIVC, LIVO, EIVO, EEVO, EEVC, LEVC, LEVO, i-EGR lift event, lift reduction, lift increase, an early extension dwell, or a late extension dwell to two or more intake valves 22 or exhaust valves 24 simultaneously.

[0097] Figures 38-41 illustrate other arrangements of rocker systems. For example, in Figure 38, rocker system 1500 is similar to rocker system 1400, but includes a first output rocker lever 1502 and a second output rocker lever 1504 that are selectively engageable with three input rocker levers 1510, 1512, 1514. In Figure 39, rocker system 1600 includes a single combined input / output rocker lever 1602 that is selectively engageable with two input rocker levers 1610, 1612.

[0098] Figure 40 illustrates a rocker system 1700 including a combined input / output rocker lever 1702, a second output rocker 1704, and two input rocker levers 1710, 1712. Figure 41 illustrates a rocker system 1800 including a single output rocker lever 1802 selectively engageable with three input rocker levers 1810, 1812, 1814.

[0099] The rocker systems 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 disclosed herein can be used with any type of valve train, including Type II, Type III, Type IV, and / or Type V valve trains. The rocker systems 100, 300, 500, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 allow for multiple operating modes on the intake and / or exhaust valves of one or more cylinders 14 of the engine 12 using a single hydraulic actuator. The operating modes can include, for example, a standard lift profile, no lift with cylinder deactivation, and an alternating lift profile. The alternating lift profiles can be for providing engine braking, such as, for example, four-stroke compression braking or two-stroke compression braking. Two-stroke compression braking valve lift profiles for the intake and exhaust valves are shown as IV2 and EV2 in Figure 3. Other alternating lift profiles are also contemplated, including LIVC, EIVC, LIVO, EIVO, EEVO, EEVC, LEVC, LEVO, i-EGR lift events, lift reduction, lift increase, early extended dwell, or late extended dwell, for one or more of the intake valves 22 and / or exhaust valves 24 other than for compression braking.

[0100] By using the rocker system of the present disclosure, the valve actuation system of any engine can be upgraded. For example, the valve actuation system can be upgraded from a standard lift function for the intake and exhaust valves to include cylinder deactivation or four-stroke compression braking. The valve actuation system can also be upgraded from a standard lift function for the intake and exhaust valves to include cylinder deactivation and four-stroke compression braking. The valve actuation system can also be upgraded from a standard lift function for the intake and exhaust valves to include cylinder deactivation and two-stroke compression braking.

[0101] During operation of the internal combustion engine system 10, the controller 80 may receive information from the various sensors listed above through the I / O interface, process the received information using a processor based on algorithms stored in the memory of the controller 80, and then send command signals to the various actuators through the I / O interface. For example, the controller 80 may receive information regarding cylinder deactivation status, engine braking request, vehicle or engine speed request, combustion conditions, post-processing temperature conditions, and / or engine load conditions. The controller 80 is configured to process the conditions and / or requests and then send one or more command signals to one or more actuators to provide cylinder deactivation and / or alternating valve lift profiles using associated camshaft lobes and input rocker levers based on a control strategy.

[0102] The controller 80 can be configured to implement the disclosed cylinder deactivation and alternating valve lift strategies using a VA system 90 incorporating the rocker system disclosed herein. In one embodiment, the disclosed method and / or controller configuration includes the controller 80 providing a cylinder deactivation command or an alternating valve lift command in response to a cylinder deactivation condition or engine operating condition based on one or more signals from one or more of the above-described sensors of the internal combustion engine system 10. The cylinder deactivation and alternating valve lift commands control the VA mechanism 90 to switch input camshaft lobes to provide a desired intake and exhaust valve closing or opening / closing lift profile and / or timing.

[0103] The control procedures performed by the controller 80 may be performed by a processor of the controller 80 executing program instructions (algorithms) stored in the memory of the controller 80. The description herein may be implemented by the internal combustion engine system 10. In certain embodiments, the internal combustion engine system 10 further includes a controller 80 structured or configured to perform certain operations to control the internal combustion engine system 10 in achieving one or more target states. In certain embodiments, the controller forms part of a process subsystem that includes one or more computing devices having memory, processing, and communication hardware. The controller may be a single device or distributed devices, and the functions of the controller 80 may be performed by hardware and / or by instructions encoded on a computer-readable medium.

[0104] In certain embodiments, the controller 80 includes one or more modules structured to functionally perform controller operations. The description herein of modules highlights structural independence from aspects of the controller and illustrates one group of controller operations and roles. Other groups performing similar overall operations are understood within the scope of this application. The modules may be implemented in hardware and / or software on a non-transitory computer-readable storage medium, and the modules may be distributed across various hardware or other computer components.

[0105] Certain operations described herein include operations for interpreting or determining one or more parameters. As used herein, interpreting or determining includes at least receiving a value by any method known in the art, including receiving a value from a data link or network communication, receiving an electronic signal (e.g., a voltage, frequency, current, or PWM signal) indicative of the value, receiving a software parameter indicative of the value, reading a value from a memory location on a non-transitory computer readable storage medium, receiving a value as a run-time parameter by means known in the art, and / or by receiving a value from which the interpreted or determined parameter can be calculated, and / or by referencing a default value that is interpreted or determined to be the parameter value.

[0106] Various aspects of the present disclosure are contemplated as set forth in the claims. In one aspect, a rocker system for an internal combustion engine is provided. The rocker system includes at least one input rocker lever rotatable about an engine component in response to motion received from at least one camshaft lobe of a camshaft, and at least one output rocker lever rotatable about the engine component. The at least one output rocker lever is configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine. The rocker system also includes at least one valve lift switch operable to connect the at least one input rocker lever and the at least one output rocker lever to one another and to disconnect the at least one input rocker lever and the at least one output rocker lever from one another to transfer motion from the at least one camshaft lobe to the at least one exhaust valve or the at least one intake valve. The rocker system also includes at least one additional input or output rocker lever connectable to the at least one output rocker lever by at least one valve lift switch.

[0107] In one embodiment, the rocker system includes a lash adjuster connecting at least one of the exhaust valve or the at least one intake valve to an output rocker lever.

[0108] In one embodiment, the at least one input rocker lever includes a first input rocker lever and a second input rocker lever each rotatable about the engine component in response to motion received from a first camshaft lobe and a second camshaft lobe, respectively, of the camshaft.

[0109] In a refinement of the above embodiment, the at least one valve lift switch is operable to connect each of the first and second input rocker levers to the at least one output rocker lever. In another refinement, the at least one valve lift switch includes a first valve lift switch for selectively connecting the first input rocker lever to the at least one output rocker lever and a second valve lift switch for selectively connecting the second input rocker lever to the at least one output rocker lever.

[0110] In a further refinement, the first valve lift switch includes a first pin assembly housed in a first bore extending between the at least one output rocker lever and the first input rocker lever. The first pin assembly includes a first valve lift pin movable within the first bore from a first position where the first valve lift pin connects the at least one output rocker lever to the first input rocker lever such that the at least one output rocker lever and the first input rocker lever rotate together about the engine component to a second position within the first bore where the first valve lift pin is housed in one of the at least one output rocker lever and the first input rocker lever such that the first input rocker lever is disconnected from the at least one output rocker lever such that rotation of the first input rocker lever is not transmitted to the at least one output rocker lever. Additionally, the second valve lift switch includes a second pin assembly housed in a second bore extending between the at least one output rocker lever and the second input rocker lever. The second pin assembly includes a second valve lift pin movable within the second bore from a first position where the second valve lift pin connects the at least one output rocker lever to the second input rocker lever such that the at least one output rocker lever and the second input rocker lever rotate together about the engine component, to a second position within the second bore where the second valve lift pin is received in one of the at least one output rocker lever and the second input rocker lever such that the second input rocker lever is disconnected from the at least one output rocker lever such that rotation of the second input rocker lever about the engine component is not transmitted to the at least one output rocker lever.

[0111] In a further refinement, in the cylinder deactivation mode of operation, the first valve lift pin and the second valve lift pin are each disposed at a second position within the first hole and the second hole, respectively, such that rotation of the first input rocker lever and rotation of the second input rocker lever about the engine component are not transmitted to the at least one output rocker lever.

[0112] In a further refinement, in a standard lift mode of operation, the first valve lift pin is positioned in the first hole at a first position and the second valve lift pin is positioned in the second hole at a second position such that rotation of the first input rocker lever about the engine component is transmitted to the at least one output rocker lever and rotation of the second input rocker lever about the engine component is not transmitted to the at least one output rocker lever.

[0113] In a further refinement, in an auxiliary lift mode of operation, at least a second valve lift pin is disposed in the second bore at a first position such that rotation of the second input rocker lever about the engine component is transmitted to the at least one output rocker lever.

[0114] In a further refinement, the first valve lift pin includes first and second shear pin portions in the first bore that are biased away from each other to a first position and movable from the first position to a second position via hydraulic fluid pressure. The valve lift pin also includes third and fourth shear pin portions in the second bore that are biased away from each other towards the second position and movable from the second position to the first position via hydraulic fluid pressure.

[0115] In a further refinement, the first valve lift pin includes first and second shear pin portions in abutting engagement with one another within the first bore, the first valve lift pin being biased to a first position and movable from the first position to a second position via hydraulic fluid pressure, and the second valve lift pin within the second bore being biased to the second position and movable from the second position to the first position via hydraulic fluid pressure.

[0116] In one embodiment, the at least one input rocker lever includes a standard lift input rocker lever rotatable about the engine component in response to motion received from a first camshaft lobe of the camshaft, a first auxiliary lift input rocker lever rotatable about the engine component in response to motion received from a second camshaft lobe of the camshaft, and a second auxiliary lift input rocker lever rotatable about the engine component in response to motion received from a third camshaft lobe of the camshaft.

[0117] In a refinement of this embodiment, the at least one output rocker lever includes a rocker body with a first arm spaced apart from a second arm. The first and second arms are configured to be disposed about the engine component to form a space between the first arm and the second arm for receiving the standard lift input rocker lever. The first auxiliary lift input rocker lever is positioned on the engine component on a side of the first arm opposite the standard lift input rocker lever, and the second auxiliary lift input rocker lever is positioned on the engine component on a side of the second arm opposite the standard lift input rocker lever.

[0118] In a refinement of the embodiment, the standard lift input rocker lever, the first auxiliary lift input rocker lever, and the second auxiliary lift input rocker lever each include a roller in direct or indirect contact with a respective one of the first, second, and third camshaft lobes of the camshaft.

[0119] In a further refinement, each of the standard lift input rocker lever, the first auxiliary lift input rocker lever, and the second auxiliary lift input rocker lever are engaged with respective first, second, and third biasing springs that contact the output rocker lever and urge the rollers into direct or indirect contact with respective first, second, and third camshaft lobes of the camshaft.

[0120] According to another aspect, a rocker system for an internal combustion engine is provided. The rocker system includes a first input rocker lever rotatable about an engine component in response to motion received from a first camshaft lobe of a camshaft, a second input rocker lever rotatable about the engine component in response to motion received from a second camshaft lobe of the camshaft, and at least one output rocker lever rotatable about the engine component. The at least one output rocker lever is configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine. The rocker system also includes a first valve lift switch and a second valve lift switch. The first valve lift switch is operable to connect the first input rocker lever to the at least one output rocker lever to transfer motion from the first camshaft lobe to the at least one exhaust valve or the at least one intake valve. The second valve lift switch is operable to connect the second input rocker lever to the at least one output rocker lever to transfer motion from the second camshaft lobe to the at least one exhaust valve or the at least one intake valve. The first and second valve lift switches are operable to disconnect the respective first and second input rocker levers from the at least one output rocker lever such that motion from the first and second camshaft lobes is not transferred to the at least one output rocker lever.

[0121] In one embodiment, the first valve lift switch is housed within a first bore extending between the at least one output rocker lever and the first input rocker lever, and the second valve lift switch is housed within a second bore extending between the at least one output rocker lever and the second input rocker lever.

[0122] In one embodiment, the first valve lift switch and the second valve lift switch are each hydraulically controlled to connect and disconnect a corresponding one of the first input rocker lever and the second input rocker lever to the at least one output rocker lever.

[0123] In one embodiment, the rocker system includes a third input rocker lever rotatable about the engine component in response to motion received from a third camshaft lobe of the camshaft. The third input rocker lever is connectable to the at least one output rocker lever by a second switch to transfer motion from the third camshaft lobe to the at least one exhaust valve or the at least one intake valve. The third rocker lever is disconnectable from the at least one output rocker lever such that motion from the third camshaft lobe is not transferred to the at least one output rocker lever.

[0124] In one embodiment, the rocker system includes a second output rocker lever rotatable about the engine component, the second output rocker lever configured to control opening and closing of at least one other exhaust valve or at least one other intake valve associated with a cylinder of the internal combustion engine, and the first switch operable to connect and disconnect the second output rocker lever from the at least one output rocker lever.

[0125] While the present invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description should be considered as illustrative and not limiting in character, with the understanding that only certain exemplary embodiments have been shown and described. Those skilled in the art will appreciate that many modifications are possible to the exemplary embodiments without materially departing from the invention. Accordingly, all such modifications are intended to be included within the scope of the present disclosure as defined in the following claims.

[0126] In reading a claim, when words such as "a," "an," "at least one," or "at least one portion" are used, it is intended that there is no intention to limit the claim to only one item, unless the claim specifically states to the contrary. When the words "at least a portion" and / or "a portion" are used, the item can include a portion and / or the entire item, unless the claim specifically states to the contrary.

Claims

1. 1. A rocker system for an internal combustion engine, comprising: at least one input rocker lever rotatable about the engine component in response to motion received from at least one camshaft lobe of the camshaft; at least one output rocker lever rotatable about the engine component, the at least one output rocker lever configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine; and At least one valve lift switch, connecting the at least one input rocker lever and the at least one output rocker lever to each other to transfer motion from the at least one camshaft lobe to the at least one exhaust valve or the at least one intake valve; at least one valve lift switch operable to disconnect the at least one input rocker lever and the at least one output rocker lever from each other; at least one additional input or output rocker lever connectable to the at least one output rocker lever by the at least one valve lift switch; a biasing mechanism in contact with the at least one input rocker lever and the at least one output rocker lever and configured to bias the at least one input rocker lever into direct or indirect contact with the at least one camshaft lobe; Equipped with each of the at least one input rocker lever includes a first stop member and each of the at least one output rocker lever includes a second stop member configured to contact a corresponding first stop member to prevent the at least one input rocker lever from over-rotating under bias of the biasing mechanism.

2. 2. The rocker system of claim 1, further comprising a lash adjuster connecting at least one of the exhaust valve or the at least one intake valve to the output rocker lever.

3. 2. The rocker system of claim 1, wherein the at least one input rocker lever comprises a first input rocker lever and a second input rocker lever each rotatable about the engine component in response to motion received from a first camshaft lobe and a second camshaft lobe, respectively, of the camshaft.

4. 4. The rocker system of claim 3, wherein the at least one valve lift switch is operable to connect each of the first and second input rocker levers to the at least one output rocker lever.

5. 4. The rocker system of claim 3, wherein the at least one valve lift switch includes a first valve lift switch for selectively connecting the first input rocker lever to the at least one output rocker lever and a second valve lift switch for selectively connecting the second input rocker lever to the at least one output rocker lever.

6. the first valve lift switch includes a first pin assembly received in a first bore extending between the at least one output rocker lever and the first input rocker lever, the first pin assembly including a first valve lift pin, the first valve lift pin being movable within the first bore from a first position where the first valve lift pin connects the at least one output rocker lever to the first input rocker lever such that the at least one output rocker lever and the first input rocker lever rotate together about the engine component, to a second position within the first bore where the first valve lift pin is received in one of the at least one output rocker lever and the first input rocker lever such that the first input rocker lever is disconnected from the at least one output rocker lever such that rotation of the first input rocker lever is not transmitted to the at least one output rocker lever; 6. The rocker system of claim 5, wherein the second valve lift switch includes a second pin assembly received in a second bore extending between the at least one output rocker lever and the second input rocker lever, the second pin assembly including a second valve lift pin, the second valve lift pin being movable within the second bore from a first position where the second valve lift pin connects the at least one output rocker lever to the second input rocker lever such that the at least one output rocker lever and the second input rocker lever rotate together about the engine component, to a second position within the second bore where the second valve lift pin is received in one of the at least one output rocker lever and the second input rocker lever such that the second input rocker lever is disconnected from the at least one output rocker lever such that rotation of the second input rocker lever about the engine component is not transmitted to the at least one output rocker lever.

7. 7. The rocker system of claim 6, wherein in a cylinder deactivated mode of operation, the first valve lift pin and the second valve lift pin are each disposed at the second position within the first hole and the second hole, respectively, such that rotation of the first input rocker lever and rotation of the second input rocker lever about the engine component are not transmitted to the at least one output rocker lever.

8. 7. The rocker system of claim 6, wherein in a standard lift mode of operation, the first valve lift pin is disposed in the first position within the first bore and the second valve lift pin is disposed in the second position within the second bore such that rotation of the first input rocker lever about the engine component is transmitted to the at least one output rocker lever and rotation of the second input rocker lever about the engine component is not transmitted to the at least one output rocker lever.

9. 7. The rocker system of claim 6, wherein in an auxiliary lift mode of operation, at least the second valve lift pin is disposed in the first position within the second bore such that rotation of the second input rocker lever about the engine component is transmitted to the at least one output rocker lever.

10. the first valve lift pin includes first and second shear pin portions within the first bore that are biased away from one another to the first position and are movable from the first position to the second position via hydraulic fluid pressure; 7. The rocker system of claim 6, wherein the valve lift pin includes third and fourth shear pin portions within the second bore biased toward the second position from each other and movable from the second position to the first position via hydraulic fluid pressure.

11. the first valve lift pin includes first and second shear pin portions in abutting engagement with one another within the first bore, the first valve lift pin being biased to the first position and movable from the first position to the second position via hydraulic fluid pressure; 7. The rocker system of claim 6, wherein the second valve lift pin in the second bore is biased to the second position and is movable from the second position to the first position via hydraulic fluid pressure.

12. The at least one input rocker lever is a standard lift input rocker lever rotatable about the engine component in response to motion received from a first camshaft lobe of the camshaft; a first auxiliary lift input rocker lever rotatable about the engine component in response to motion received from a second camshaft lobe of the camshaft; a second auxiliary lift input rocker lever rotatable about said engine component in response to motion received from a third camshaft lobe of said camshaft.

13. 13. The rocker system of claim 12, wherein the at least one output rocker lever includes a rocker body with a first arm spaced from a second arm, the first and second arms configured to be disposed about the engine component and defining a space between the first arm and the second arm for receiving the standard lift input rocker lever, the first auxiliary lift input rocker lever positioned on the engine component on a side of the first arm opposite the standard lift input rocker lever, and the second auxiliary lift input rocker lever positioned on the engine component on a side of the second arm opposite the standard lift input rocker lever.

14. 14. The rocker system of claim 13, wherein the standard lift input rocker lever, the first auxiliary lift input rocker lever, and the second auxiliary lift input rocker lever each include a roller in direct or indirect contact with a respective one of the first, second, and third camshaft lobes of the camshaft.

15. 15. The rocker system of claim 14, wherein each of the standard lift input rocker lever, the first auxiliary lift input rocker lever, and the second auxiliary lift input rocker lever are engaged with respective first, second, and third biasing springs forming the biasing mechanism, the first, second, and third biasing springs contacting the output rocker lever to bias the roller into direct or indirect contact with the respective first, second, and third camshaft lobes of the camshaft.

16. 1. A rocker system for an internal combustion engine, comprising: a first input rocker lever rotatable about the engine component in response to motion received from a first camshaft lobe of the camshaft; a second input rocker lever rotatable about an engine component in response to motion received from a second camshaft lobe of the camshaft; at least one output rocker lever rotatable about the engine component, the at least one output rocker lever configured to control opening and closing of at least one exhaust valve or at least one intake valve associated with a cylinder of the internal combustion engine; and a first valve lift switch and a second valve lift switch, the first valve lift switch is operable to connect the first input rocker lever to the at least one output rocker lever to transfer motion from the first camshaft lobe to the at least one exhaust valve or the at least one intake valve; the second valve lift switch is operable to connect the second input rocker lever to the at least one output rocker lever to transfer motion from the second camshaft lobe to the at least one exhaust valve or the at least one intake valve; first and second valve lift switches operable to disconnect the respective first and second input rocker levers from the at least one output rocker lever such that motion from the first and second camshaft lobes is not transmitted to the at least one output rocker lever; a biasing mechanism in contact with the first input rocker lever, the second input rocker lever, and the at least one output rocker lever, configured to bias the first input rocker lever and the second input rocker lever into direct or indirect contact with the first camshaft lobe and the second camshaft lobe, respectively; Equipped with each of the first input rocker lever and the second input rocker lever includes a first stop member and each of the at least one output rocker lever includes a second stop member configured to contact a corresponding first stop member to prevent the first input rocker lever and the second input rocker lever from over-rotating under bias of the biasing mechanism.

17. the first valve lift switch is received within a first bore extending between the at least one output rocker lever and the first input rocker lever; 17. The rocker system of claim 16, wherein the second valve lift switch is housed within a second bore extending between the at least one output rocker lever and the second input rocker lever.

18. 17. The rocker system of claim 16, wherein the first valve lift switch and the second valve lift switch are each hydraulically controlled to connect and disconnect a corresponding one of the first input rocker lever and the second input rocker lever to the at least one output rocker lever.

19. a third input rocker lever rotatable about the engine component in response to motion received from a third camshaft lobe of the camshaft; the third input rocker lever is connectable by the second switch to the at least one output rocker lever to transfer motion from the third camshaft lobe to the at least one exhaust valve or the at least one intake valve; 17. The rocker system of claim 16, wherein the third rocker lever is disconnectable from the at least one output rocker lever such that motion from the third camshaft lobe is not transmitted to the at least one output rocker lever.

20. a second output rocker lever rotatable about the engine component, the second output rocker lever configured to control opening and closing of at least one other exhaust valve or at least one other intake valve associated with a cylinder of the internal combustion engine; 17. The rocker system of claim 16, wherein the first switch is operable to connect and disconnect the second output rocker lever from the at least one output rocker lever.

21. A rocker system as described in claim 1, wherein each of the first stop members is provided with a stop pin.

22. A rocker system as described in claim 1, wherein each of the second retaining members has a retaining member protrusion.

23. A rocker system as described in claim 16, wherein each of the first stop members includes a stop pin.

24. A rocker system as described in claim 16, wherein each of the second retaining members has a retaining member protrusion.

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