Patent Document

CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority to U.S. Provisional Patent Application Ser. No. 62/347,870, filed on Jun. 9, 2016. The entire contents of the above-referenced application are hereby incorporated by reference in its entirety for all purposes. 
     
    
     FIELD 
       [0002]    The present description relates to systems and methods for selectively deactivating and reactivating one or more cylinders of an internal combustion engine. The systems and methods may be applied to engines that operate poppet valves to control flow into and out of engine cylinders. 
       BACKGROUND AND SUMMARY 
       [0003]    Valves of an engine cylinder may be activated and deactivated from time to time to increase vehicle fuel economy and provide a desired torque. Valve operators that activate and deactivate the valves may be designed such that they cannot overcome valve spring forces when the valves are open. Therefore, the valves may have to be deactivated and activated at precise time intervals or the valves may activate or deactivate in a different engine cycle than is desired. Further, it may be desirable to deactivate the cylinders such that exhaust gases are expelled from the cylinder before the cylinder is deactivated and fresh air is inducted into the cylinder before reactivating the cylinder. However, it may be costly and difficult to timely activate and deactivate engine cylinders so that a desired engine power or torque may be provided. 
         [0004]    The inventor herein has recognized the above-mentioned disadvantages and has developed an engine system, comprising: a camshaft saddle including a stationary groove; and a camshaft including a discontinuous groove; the camshaft fitted to the camshaft saddle, the stationary groove aligned with the discontinuous groove. 
         [0005]    By installing a discontinuous groove in a camshaft, it may be possible to provide the technical result of timely activating and deactivating cylinder valves with reduced cost as compared to valves that are solely activated and deactivated based on timing of operating an electrically actuated valve. In particular, since the discontinuous groove rotates synchronously with the camshaft, the discontinuous groove may provide oil flow to a deactivating valve operator without having to open a valve dedicated to operating only the one valve operator. Instead, a single electrically operated valve may control two deactivating valve operators that activate and deactivate intake and exhaust valves. Consequently, the valves may be timely activated and deactivated via a single electrically operated valve. 
         [0006]    The present description may provide several advantages. Specifically, the approach may reduce valve train complexity. Further, the approach may reduce valve system cost. Further still, the approach may reduce computational load on a controller. 
         [0007]    The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings. 
         [0008]    It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The advantages described herein will be more fully understood by reading an example of an embodiment, referred to herein as the Detailed Description, when taken alone or with reference to the drawings, where: 
           [0010]      FIG. 1  is a schematic diagram of a single cylinder of an engine; 
           [0011]      FIG. 2A  shows an example camshaft for a hydraulically operated valve deactivating system; 
           [0012]      FIG. 2B  shows a cross section of the camshaft and a camshaft saddle for the hydraulically operated valve deactivating system shown in  FIG. 2A ; 
           [0013]      FIG. 2C  shows an example valve operator for the hydraulically operated valve deactivating system shown in  FIG. 2A   
           [0014]      FIG. 2D  shows example valve deactivating valve operators for the hydraulically operated valve deactivating system shown in  FIG. 2A ; 
           [0015]      FIG. 2E  is an example cylinder and valve deactivation sequence for the hydraulically operated valve deactivating system shown in  FIG. 2A ; and 
           [0016]      FIG. 3  is a flowchart of an example method for operating an engine with deactivating cylinders and valves. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The present description is related to systems and methods for selectively activating and deactivating cylinders and cylinder valves of an internal combustion engine. The engine may be configured and operate as discussed in the description of  FIGS. 1-2D . A prophetic operating sequence for an engine that includes deactivating valves is shown in  FIG. 2E . The method of  FIG. 3  provides for activating and deactivating selected intake and exhaust valves of engine cylinders. 
         [0018]    Referring to  FIG. 1 , internal combustion engine  10 , comprising a plurality of cylinders, one cylinder of which is shown in  FIG. 1 , is controlled by electronic engine controller  12 . Engine  10  is comprised of cylinder head casting  35  and block  33 , which include combustion chamber  30  and cylinder walls  32 . Piston  36  is positioned therein and reciprocates via a connection to crankshaft  40 . Flywheel  97  and ring gear  99  are coupled to crankshaft  40 . Starter  96  (e.g., low voltage (operated with less than 30 volts) electric machine) includes pinion shaft  98  and pinion gear  95 . Pinion shaft  98  may selectively advance pinion gear  95  to engage ring gear  99 . Starter  96  may be directly mounted to the front of the engine or the rear of the engine. In some examples, starter  96  may selectively supply torque to crankshaft  40  via a belt or chain. In one example, starter  96  is in a base state when not engaged to the engine crankshaft. 
         [0019]    Combustion chamber  30  is shown communicating with intake manifold  44  and exhaust manifold  48  via respective intake valve  52  and exhaust valve  54 . Each intake and exhaust valve may be operated by camshaft  51 . Each intake valve  52  is in mechanical communication with camshaft  51  via intake valve operator  59 . Each exhaust valve  54  is in mechanical communication with camshaft  51  via exhaust valve operator  57 . Valve operators described in greater detail below may transfer mechanical energy from camshaft  51  to intake valve  52  and to exhaust valve  54 . Optionally, the engine may include intake and exhaust camshafts where only the exhaust camshaft or the intake camshaft include a discontinuous groove. 
         [0020]    Fuel injector  66  is shown positioned to inject fuel directly into cylinder  30 , which is known to those skilled in the art as direct injection. Optional fuel injector  67  is shown positioned to port inject fuel to cylinder  30 , which is known to those skilled in the art as port fuel injection. Fuel injectors  66  and  67  deliver liquid fuel in proportion to pulse widths from controller  12 . Fuel is delivered to fuel injectors  66  and  67  by a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail (not shown). In one example, a high pressure, dual stage, fuel system may be used to generate higher fuel pressures. 
         [0021]    In addition, intake manifold  44  is shown communicating with optional turbocharger compressor  162  and engine air intake  42 . In other examples, compressor  162  may be a supercharger compressor. Shaft  161  mechanically couples turbocharger turbine  164  to turbocharger compressor  162 . Optional electronic throttle or central throttle  62  adjusts a position of throttle plate  64  to control air flow from compressor  162  to intake manifold  44 . Pressure in boost chamber  45  may be referred to a throttle inlet pressure since the inlet of throttle  62  is within boost chamber  45 . The throttle outlet is in intake manifold  44 . Compressor recirculation valve  47  may be selectively adjusted to a plurality of positions between fully open and fully closed. Waste gate  163  may be adjusted via controller  12  to allow exhaust gases to selectively bypass turbine  164  to control the speed of compressor  162 . Air filter  43  cleans air entering engine air intake  42 . 
         [0022]    Distributorless ignition system  88  provides an ignition spark to combustion chamber  30  via spark plug  92  in response to controller  12 . Universal Exhaust Gas Oxygen (UEGO) sensor  126  is shown coupled to exhaust manifold  48  upstream of catalytic converter  70 . Alternatively, a two-state exhaust gas oxygen sensor may be substituted for UEGO sensor  126 . 
         [0023]    Converter  70  can include multiple catalyst bricks, in one example. In another example, multiple emission control devices, each with multiple bricks, can be used. Converter  70  can be a three-way type catalyst in one example. Further, converter  70  may include a particulate filter. 
         [0024]    Controller  12  is shown in  FIG. 1  as a conventional microcomputer including: microprocessor unit  102 , input/output ports  104 , read-only memory  106  (e.g., non-transitory memory), random access memory  108 , keep alive memory  110 , and a conventional data bus. Controller  12  is shown receiving various signals from sensors coupled to engine  10 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor  112  coupled to cooling sleeve  114 ; a position sensor  134  coupled to an accelerator pedal  130  for sensing force applied by foot  132 ; a position sensor  154  coupled to brake pedal  150  for sensing force applied by foot  152 , a measurement of engine manifold pressure (MAP) from pressure sensor  122  coupled to intake manifold  44 ; an engine position sensor from a Hall effect sensor  118  sensing crankshaft  40  position; a measurement of air mass entering the engine from sensor  120 ; and a measurement of throttle position from sensor  68 . Barometric pressure may also be sensed (sensor not shown) for processing by controller  12 . In a preferred aspect of the present description, engine position sensor  118  produces a predetermined number of equally spaced pulses every revolution of the crankshaft from which engine speed (RPM) can be determined. 
         [0025]    During operation, each cylinder within engine  10  typically undergoes a four stroke cycle: the cycle includes the intake stroke, compression stroke, expansion stroke, and exhaust stroke. A cylinder cycle for a four stroke engine is two engine revolutions and an engine cycle is also two revolutions. During the intake stroke, generally, the exhaust valve  54  closes and intake valve  52  opens. Air is introduced into combustion chamber  30  via intake manifold  44 , and piston  36  moves to the bottom of the cylinder so as to increase the volume within combustion chamber  30 . The position at which piston  36  is near the bottom of the cylinder and at the end of its stroke (e.g. when combustion chamber  30  is at its largest volume) is typically referred to by those of skill in the art as bottom dead center (BDC). 
         [0026]    During the compression stroke, intake valve  52  and exhaust valve  54  are closed. Piston  36  moves toward the cylinder head casting  35  so as to compress the air within combustion chamber  30 . The point at which piston  36  is at the end of its stroke and closest to the cylinder head casting  35  (e.g. when combustion chamber  30  is at its smallest volume) is typically referred to by those of skill in the art as top dead center (TDC). In a process hereinafter referred to as injection, fuel is introduced into the combustion chamber. In a process hereinafter referred to as ignition, the injected fuel is ignited by known ignition means such as spark plug  92 , resulting in combustion. 
         [0027]    During the expansion stroke, the expanding gases push piston  36  back to BDC. Crankshaft  40  converts piston movement into a rotational torque of the rotary shaft. Finally, during the exhaust stroke, the exhaust valve  54  opens to release the combusted air-fuel mixture to exhaust manifold  48  and the piston returns to TDC. Note that the above is shown merely as an example, and that intake and exhaust valve opening and/or closing timings may vary, such as to provide positive or negative valve overlap, late intake valve closing, or various other examples. 
         [0028]    Driver demand torque may be determined via a position of accelerator pedal  130  and vehicle speed. For example, accelerator pedal position and vehicle speed may index a table that outputs a driver demand torque. The driver demand torque may represent a desired engine torque or torque at a location along a driveline that includes the engine. Engine torque may be determined from driver demand torque via adjusting the driver demand torque for gear ratios, axle ratios, and other driveline components. 
         [0029]    Referring now to  FIG. 2A , a camshaft for a hydraulically operated valve deactivating system is shown. Camshaft  51  may be included in the engine system shown in  FIG. 1 . In this example the camshaft operates valves for four cylinders, which may be all cylinders on a four cylinder engine, or one bank of a V-8 engine. Other configurations for other greater or fewer cylinder counts are possible. 
         [0030]    In this example, camshaft  51  operates both intake and exhaust valves. In engines where separate intake and exhaust camshaft, the depicted camshaft could refer to either the intake or exhaust camshaft. The intake and exhaust valves of each engine cylinder may be individually activated and deactivated. Camshaft  51  includes sprocket  219  that allows crankshaft  40  of  FIG. 1  to drive camshaft  51  via a chain. Camshaft  51  includes four journals  205   a - 205   d  (e.g., a journal for each engine cylinder on a cylinder bank), which include lands  206   a - 206   d , and discontinuous grooves  208   a - 208   d . Camshaft saddle  202  includes stationary grooves  210   a  (shown in  FIG. 2B ) for each of valve bodies  270   a ,  270   b ,  270   c , and  270   d . The stationary grooves  210   a  are situated to axially align with discontinuous grooves  208   a - 208   d . Camshaft  51  also includes cam lobes. In one example, camshaft  51  may operate both intake and exhaust valves as camshaft  51  rotates. In particular, lobe  220  operates an intake valve of cylinder number one and lobe  222  operates an exhaust valve of cylinder number one. Lobe  238  operates an intake valve of cylinder number two and lobe  239  operates an exhaust valve of cylinder number two. Lobe  248  operates an intake valve of cylinder number three and lobe  249  operates an exhaust valve of cylinder number three. Lobe  258  operates an intake valve of cylinder number four and lobe  259  operates an exhaust valve of cylinder number four. 
         [0031]    Camshaft saddle  202  includes valve bodies  270   a ,  270   b ,  270   c , and  270   d  to support and provide oil passages leading to the camshaft discontinuous grooves. In particular, valve body  270   a  includes inlet  213 , first outlet  212 , and second outlet  216 . First outlet  212  provides oil to exhaust valve operators via a conduit. Second outlet  216  provides oil to intake valve operators via a conduit. Valve body  270   b  includes inlet  233 , first outlet  236 , and second outlet  232 . First outlet  236  provides oil to exhaust valve operators via a conduit. Second outlet  232  provides oil to intake valve operators via a conduit. Valve body  270   c  includes inlet  243 , first outlet  246 , and second outlet  242 . First outlet  246  provides oil to exhaust valve operators via a conduit. Second outlet  242  provides oil to intake valve operators via a conduit. Valve body  270   d  includes inlet  253 , first outlet  256 , and second outlet  252 . First outlet  256  provides oil to exhaust valve operators via a conduit. Second outlet  252  provides oil to intake valve operators via a conduit. Passages  216 ,  232 ,  242 , and  252  supply pressurize oil from oil pump  290  to intake valve operators  249  (shown in  FIG. 2C ) via gallery or passage  292  for respective cylinder numbers 1-4 when control valves  214 ,  234 ,  244 , and  254  are activated and open. Outlets  212 ,  236 ,  246 , and  256  may supply oil pressure to exhaust valve operators  248  (shown in  FIG. 2C ) when control valves  214 ,  234 ,  244 , and  254  are open. Discontinuous grooves  208   a - 208   d  selectively provide an oil path between inlets  213 ,  233 ,  243 , and  253  and valve body outlets  212 ,  236 ,  246 , and  256  that lead to exhaust valve operators. Journals  205   a - 205   d  are partially circumscribed by discontinuous grooves  208   a - 208   d . Accumulators  209   a - 209   d  provide oil to keep exhaust valves deactivated when land  206   a  covers passage  212  for short periods of time. 
         [0032]    Referring now to  FIG. 2B , a cross section valve body  270   a  and its associated components is shown. Each valve body of camshaft saddle  202  is constructed similarly, but lands like  206   a  are phased differently from land  206   a . Camshaft  51  is coupled to camshaft saddle  202  via cap  299 . Cap  299  covers stationary groove  210   a  formed in camshaft saddle  202 , and cap  299  includes an oil outlet  298 . Camshaft  51  includes discontinuous groove  208   a  that is axially aligned with stationary groove  210   a . Valve  214  selectively allows oil to flow to intake valve operators via passage  216  and into stationary groove  210   a . Land  206   a  selectively covers and uncovers outlet  212  which provides oil to accumulator  209   a  and exhaust valve operators as camshaft  51  rotates. Accumulator  209   a  maintains oil pressure at outlet  212  when land  206   a  is covering outlet  212 . 
         [0033]    Referring now to  FIG. 2C , example deactivating intake valve operator  59  and exhaust valve operator  57  for the hydraulically operated valve deactivating system shown in  FIGS. 1 and 2A  are shown. Camshaft  51  rotates so that lobe  220  selectively lifts intake follower  245 , which selectively opens and closes intake valve  52 . Rocker shaft  244  provides a selective mechanical linkage between intake follower  245  and intake valve contactor  247 . Passage  246  allows pressurized oil to reach a piston shown in  FIG. 2D  so that intake valve  52  may be deactivated (e.g., remain in a closed position during an engine cycle). Intake valve  52  may be activated when oil pressure in passage  246  is low. 
         [0034]    Similarly, camshaft  51  rotates so that lobe  222  selectively lifts exhaust follower  243 , which selectively opens and closes exhaust valve  54 . Rocker shaft  242  provides a selective mechanical linkage between exhaust follower  243  and exhaust valve contactor  240 . Passage  241  allows pressurized oil to reach a piston shown in  FIG. 2D  so that exhaust valve  54  may be deactivated (e.g., remain in a closed position during an engine cycle). Exhaust valve  54  may be activated when oil pressure in passage  241  is low. 
         [0035]    Referring now to  FIG. 2D , an example exhaust valve operator  248  is shown. Intake valve operators include similar components and operate similar to the way the exhaust valve actuator operates. Therefore, for the sake of brevity, a description of intake valve operators is omitted. Exhaust follower  243  is shown with oil passage  265 , which extends within camshaft follower  264 . Oil passage  265  fluidly communicates with port  268  in rocker shaft  242 . Piston  263  and latching pin  261  selectively lock follower  243  to exhaust valve contactor  240 , which causes exhaust valve contactor  240  to move in response to the motion of follower  243  when oil is not acting on piston  263 . The exhaust valve operator  248  is in an activated state during such conditions. 
         [0036]    Piston  263  may be acted upon by oil pressure within oil passages  267  and  265 . Piston  263  is forced from its at-rest position shown in  FIG. 2C  (e.g., its normally activated state) by high pressure oil in passage  265  acting against force of spring  269  to its deactivated state. Spring  269  biases piston  263  into a normally locked position that allows exhaust valve contactor  240  to operate an exhaust valve  54  when oil pressure in passage  565  is low. 
         [0037]    Latching pin  261  stops at a position (e.g., unlocked position) where follower  243  is no longer locked to exhaust valve contactor  240 , thereby deactivating exhaust valve  54  when normally locked latching pin  261  is fully displaced by high pressure oil operating on piston  263 . Camshaft follower  243  is rocked according to the movement of cam lobe  222  when exhaust valve operator  248  is in a deactivated state. Exhaust valve  54  and exhaust valve contactor  240  remain stationary when piston latching pin  261  is in its unlocked positon. 
         [0038]    Thus, oil pressure may be used to selectively activate and deactivate intake and exhaust valves via intake and exhaust valve operators. Specifically, intake and exhaust valves may be deactivated by allowing oil to flow to the intake and exhaust valve operators. It should be noted that intake and exhaust valve operators may be activated and deactivated via the mechanism shown in  FIG. 2D .  FIGS. 2C and 2D  depict rocker shaft mounted deactivating valve actuators. Other types of deactivating valve actuators are possible and compatible with the invention including deactivating roller finger followers, deactivating lifters, or deactivating lash adjusters. 
         [0039]    Referring now to  FIG. 2E , a valve and cylinder deactivation sequence for the mechanism of  FIGS. 2A-2D  is shown. The valve deactivation sequence may be provided by the system of  FIGS. 1-2D . 
         [0040]    The first plot from the top of  FIG. 2E  is a plot of exhaust cam groove width at the passage leading to the exhaust valve operator versus crankshaft angle. The vertical axis represents exhaust camshaft groove width and groove width increases in the direction of the vertical axis arrow. The horizontal axis represents engine crankshaft angle, where zero is top-dead-center compression stroke for the cylinder whose intake and exhaust grooves are shown. In this example, the exhaust groove corresponds to the width of groove  208   a  of  FIG. 2A  measured at the oil outlet passage  212 . The crankshaft angles for the exhaust groove width are the same as the crankshaft angle in the second plot from the top of  FIG. 2E . 
         [0041]    The second plot from the top of  FIG. 2E  is a plot of intake and exhaust valve lift versus engine crankshaft angle. The vertical axis represents valve lift and valve lift increases in the direction of the vertical axis arrow. The horizontal axis represents engine crankshaft angle and the two plots are aligned according to crankshaft angle. Thin solid line  290  represents intake valve lift for cylinder number one when its intake valve operator is activated. Thick solid line  291  represents exhaust valve lift for cylinder number one when its exhaust valve operator is activated. Thin dashed lines  292  represent intake valve lift for cylinder number one if its intake valve operator were activated. Thick dashed line  293  represents exhaust valve lift for cylinder number one if its exhaust valve operator were activated. Vertical lines A-D represent crankshaft angles of interest for the sequence. 
         [0042]    The intake valve lift for cylinder number one is shown increasing and then decreasing before crankshaft angle A. An oil control valve, such as  214  of  FIG. 2A , is closed before crankshaft angle A to prevent intake and exhaust valve deactivation. The intake valve lift  290  is shown increasing during cylinder number one&#39;s intake stroke before crankshaft angle A. Pressurized oil sufficient to deactivate intake valves is not present in oil passage  216  before crankshaft angle A. 
         [0043]    At crankshaft angle A, the oil control valve (e.g.,  214  of  FIG. 2A ) may be opened to deactivate intake and exhaust valves. The stationary groove (e.g.,  208   a  of  FIG. 2B ) and passage  216  are pressurized with oil after the oil control valve is opened so that the intake valve operator latching pin may be displaced while the outlet  298  is covered via land  206   a . Thus, outlet passage  298  is not pressurized with oil at angle A because the land  206   a  (shown in  FIG. 2A ) covers the valve body outlet  298 . Therefore, only the intake valve begins to be deactivated at crankshaft angle A. The intake valve operator latching pin is disengaged from its normal position before crankshaft angle C to prevent the intake valve from opening. 
         [0044]    At crankshaft angle B, the land of the exhaust camshaft land  206   a  for cylinder number one makes way for the discontinuous groove  208   a , which allows oil to reach the outlet  298  and exhaust valve operator for cylinder number one. Oil can flow to the intake valve operator and the exhaust valve operator at crankshaft angle B, but since the exhaust valve is partially lifted at crankshaft angle B, the exhaust valve operates until the exhaust valve closes near crankshaft angle C. The exhaust valve operator latching pin is disengaged from its normally engaged position before crankshaft angle D to prevent the exhaust valve from opening. 
         [0045]    At crankshaft angle C, the intake valve does not open since the intake valve operator is deactivated for the engine cycle. Further, the exhaust valve operator latching pin is disengaged from its normal position before crankshaft angle D to prevent the exhaust valve from opening. Consequently, the exhaust valve does not open for the cylinder cycle. The intake and exhaust valves may remain deactivated until the intake and exhaust operators are reactivated by reducing oil pressure to the intake and exhaust valve operators. 
         [0046]    The intake and exhaust valve may be reactivated via deactivating the oil control valve  214  and allowing oil pressure in the intake and exhaust valve operators to be reduced or via dumping oil pressure from the intake and exhaust valve operators via a dump valve (not shown). 
         [0047]    Oil accumulator  209   a  maintains oil pressure in oil passage  212  during the portion of the cycle after crankshaft angle D when the exhaust cam groove land blocks passage  298 . The accumulator  209   a  compensates for oil leakage through various clearances during the time when oil supply from the pump is interrupted. The oil accumulator  209   a  may include a dedicated piston and spring or may be combined with the latch pin mechanism such as the mechanism depicted in  FIG. 2D . The inputs and outputs for the valve bodies described in  FIGS. 2A-2D  may also be referred to as ports. 
         [0048]    Thus, the system of  FIGS. 1-2C  provides for an engine system, comprising: a camshaft saddle including a stationary groove; and a camshaft including a discontinuous groove; the camshaft fitted to the camshaft saddle, the stationary groove aligned with the discontinuous groove. The engine system includes where the discontinuous groove is oriented axially along the camshaft. The engine system further comprises an oil inlet port in fluidic communication with the stationary groove. The engine system includes where the oil inlet port is located along the camshaft saddle. The engine system further comprises an oil pump supplying oil to the oil inlet port. The engine system further comprises an oil control valve, the oil control valve located along an oil gallery leading from the oil pump to the oil inlet port. The engine system further comprises an oil outlet port located along the camshaft saddle. The engine system includes where the oil outlet port is in fluidic communication with an intake valve operator. 
         [0049]    The system of  FIGS. 1-2C  also provides for an engine system, comprising: a camshaft including a first discontinuous groove, and a second discontinuous groove; a first valve body including a first stationary groove and a first inlet port and a first outlet port; a first intake valve operator in mechanical communication with the camshaft and in fluidic communication with the first discontinuous groove; a second valve body including a second stationary groove and a second inlet port and a second outlet port; and a second intake valve operator in mechanical communication with the camshaft and in fluidic communication with the second discontinuous groove. The engine system further comprises a first valve positioned along a conduit between the first valve body and an oil pump, a second valve positioned along the conduit between the second valve body and the oil pump. The engine system further comprises a controller including executable instructions stored in non-transitory memory, which when executed by the controller, open the first valve independent from opening the second valve. The engine system further comprises additional instructions to open the second valve at a same time the first valve is opened. The engine system further comprises a first exhaust valve operator in mechanical communication with the camshaft and in fluidic communication with the first stationary groove. The engine system includes where the first discontinuous groove is positioned to inhibit oil flow to an exhaust valve operator between exhaust valve closing of a cylinder and intake valve opening of the cylinder. 
         [0050]    The system of  FIGS. 1-2C  also provides for a vehicle system, comprising: an engine including a camshaft with a discontinuous groove; a valve operator in mechanical communication with an exhaust valve and in fluidic communication with the discontinuous groove; and a camshaft journal cap. The vehicle system includes where the journal cap includes an oil exit port. The vehicle system further comprises an accumulator in fluidic communication with the oil exit port. The vehicle system includes where the oil exit port is in fluidic communication with an exhaust valve operator. The vehicle system includes where the discontinuous groove is circumferential. The vehicle system includes where the discontinuous groove is axially oriented on the camshaft. 
         [0051]    Referring now to  FIG. 3 , a method for operating an engine with deactivating cylinders and valves is shown. The method of  FIG. 3  may be included in the system described in  FIGS. 1-2C . The method may be included as executable instructions stored in non-transitory memory. The method of  FIG. 3  may perform in cooperation with system hardware and other methods described herein to transform an operating state of an engine or its components. 
         [0052]    At  302 , method  300  determines engine operating conditions. Engine operating conditions may include but are not limited to engine speed, engine torque, requested engine torque, barometric pressure, engine temperature, and ambient temperature. Method  300  proceeds to  304  after determining engine operating conditions. 
         [0053]    At  304 , method  300  judges if cylinder deactivation is requested. In one example, cylinder deactivation may be requested based on engine speed, requested engine torque, and engine temperature. If engine operating conditions for deactivating engine cylinders are present, the answer is yes and method  300  proceeds to  306 . Otherwise, the answer is no and method  300  proceeds to  310 . 
         [0054]    At  310 , method  300  closes all oil control valves for deactivating cylinders. Deactivating the oil control valves ceases oil flow from the engine oil pump to intake and exhaust valve deactivating operators. If an oil control valve was previously opened, it may be closed at a specific time to align near angle A of  FIG. 2E  to ensure that a cylinder&#39;s intake valve starts lifting before the cylinder&#39;s exhaust valve. Consequently, oil pressure in oil galleries leading to the intake and exhaust valve operators decreases and all engine intake and exhaust valves are activated. Method  300  proceeds to exit. 
         [0055]    At  306 , method  300  determines which engine cylinders to deactivate. In on example, a map of cylinders to deactivate is indexed by engine speed and requested engine torque. The map or table stored in controller memory outputs which engine cylinders are to be deactivated. Method  300  proceeds to  308 . 
         [0056]    At  308 , method  300  opens oil control valves to supply oil to the cylinder to be deactivated as determined at  306 . The method closes the oil control valves related to cylinders that will not be deactivated. The timing of opening and closing oil control valves for each cylinder may occur at specific times to align near angle A of  FIG. 2E  to ensure that the intake valve changes state before the exhaust valve. The actual total number of cylinders deactivated may vary between engine operating conditions. For example, if the engine is a four cylinder engine with a firing order of 1-3-4-2, cylinders 1 and 4 may be deactivated during one engine cycle and cylinders 3 and 2 may be deactivated during a different engine cycle. Method  300  proceeds to exit after opening the oil control valves. 
         [0057]    In this way, cylinder valves of an engine may be activated and deactivated. Further, the number of cylinders and the pattern of cylinders deactivated may vary from engine cycle to engine cycle. 
         [0058]    Note that the example control and estimation routines included herein can be used with various engine and/or vehicle system configurations. The control methods and routines disclosed herein may be stored as executable instructions in non-transitory memory and may be carried out by the control system including the controller in combination with the various sensors, actuators, and other engine hardware. The specific routines described herein may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various actions, operations, and/or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations and/or functions may be repeatedly performed depending on the particular strategy being used. Further, at least a portion of the described actions, operations and/or functions may graphically represent code to be programmed into non-transitory memory of the computer readable storage medium in the control system. The control actions may also transform the operating state of one or more sensors or actuators in the physical world when the described actions are carried out by executing the instructions in a system including the various engine hardware components in combination with one or more controllers. 
         [0059]    This concludes the description. The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description. For example, I3, I4, I5, V6, V8, V10, and V12 engines operating in natural gas, gasoline, diesel, or alternative fuel configurations could use the present description to advantage.

Technology Category: 2