Abstract:
A required valve timing change rate Vreq is calculated so as to make a deviation D between a target valve timing VTtg and an actual valve timing VT small and then a required speed difference DMCRreq between a motor 26 and a camshaft 16 is calculated on a basis of the required valve timing change rate Vreq. When the deviation D is larger than a predetermined value, a required motor speed Rmreq is calculated by adding the required speed difference DMCRreq to a camshaft speed RC and a motor control value is calculated so as to control the motor speed RM to the required motor speed Rmreq. When the deviation D is not larger than the predetermined value, the camshaft speed RC is set as the required motor speed Rmreq and the motor control value is calculated so as to control the motor speed RM to the camshaft speed RC.
Abstract:
A real-time control system having a fixed loop time is provided. The system includes an input having frequency ranging both above and below the fixed loop time; and a method for utilizing information provided by a pulse wheel and sensed by a sensor. The method includes the steps of: providing a rotating shaft; providing a pulse wheel rigidly affixed onto the rotating shaft; providing a sensor sensing an information out of the pulse wheel, the sensed information comprising a first information and a second information; and when the rotating rate of the rotating shaft is greater than a predetermined value, averaging at least two pulses wherein one of the at least two pulses being related to the first information and at least one pulse being related to the second information; thereby, the second information is used along with the first information for a more accurate representation of the information.
Abstract:
A variable valve control system for an internal combustion engine including a plurality of cylinders, the variable valve control system including a variable lift characteristic control mechanism to adjust a valve lift characteristic of each of intake valves. The variable valve control system is configured to perform determining an engine condition indicator in correlation with an actual relative variation in the valve lift characteristic between the cylinders; determining a desired valve lift characteristic in accordance with an operating condition of the internal combustion engine; controlling the valve lift characteristic of each of the intake valves in accordance with the desired valve lift characteristic; determining the engine condition indicator when the desired valve lift characteristic is equal to a predetermined small valve lift characteristic setting; and expanding the small valve lift characteristic setting if the determined engine condition indicator is larger than a predetermined first threshold value.
Abstract:
A camshaft adjusting device for internal combustion engines of motor vehicles has an intake camshaft adjuster and an exhaust camshaft adjuster driven by an endless drive connected to the crankshaft. The intake and exhaust camshaft adjusters are connected by a gear transmission to one another. The intake and exhaust camshaft adjusters each have a gear forming a part of the gear transmission. The intake and exhaust camshaft adjusters are directly drivingly connected by the gears or a common gear wheel fixedly connected to an intermediate shaft is positioned between the gears.
Abstract:
An electromagnetic spool valve includes a spool valve, an electromagnetic actuator, and a bracket. The spool valve includes a cylindrical sleeve and a spool. The cylindrical sleeve includes an input/output ports for fluid to flow through. The spool is axially slidable in the sleeve. The electromagnetic actuator is fixed to the spool valve for axially driving the spool. The bracket is welded to the electromagnetic actuator. The spool valve is disposed in a fixing member and is fixed thereto by a tightening member tightening the bracket welded to the yoke to the fixing member. Either the bracket or the electromagnetic actuator includes a stopper contact portion for contacting a part of the other to prevent the electromagnetic spool valve from being removed from the sleeve insertion hole.
Abstract:
Based on results of a knock control for adjusting ignition timing in accordance with the occurrence of knocking, an electronic control unit computes deposit required ignition timing akgrg, which is ignition timing determined by taking adhesion of deposits in an internal combustion engine into consideration. Based on the deposit required ignition timing akgrg, the electronic control unit reduces a vvt allowable variable range of a target VVT advancement amount, which is a control target value of a variable valve timing mechanism. The electronic control unit corrects a required ignition timing based on the actual VVT advancement amount vt, which is chanted according to the reduction of the allowable variable range of the target VVT advancement amount. As a result, problems resulting from the adhesion of deposits are effectively avoided.
Abstract:
An internal combustion engine for an outboard motor that comprises at least one combustion chamber formed by at least a engine body, a cylinder head assembly and a piston that moves relative to the engine body and the cylinder head assembly. A crankshaft extends in a generally vertical direction and is coupled to the piston such that movement of the piston causes the crankshaft to rotate. A camshaft is journaled for rotation and extends generally parallel to the crankshaft. The camshaft includes at least one cam configured to open and close a valve. A control valve for a variable valve timing mechanism is positioned within a common hydraulic passage having a first opening and a second opening. The control valve is positioned generally along an axis that is perpendicular to the camshaft.
Abstract:
A line of small internal combustion engines, including twin cylinder engines and single cylinder engines. The engines each include a crankcase, and one or more cylinder members attached to the crankcase, the cylinder members being separate components from the crankcase. A number of different crankcases are provided for various types of single and two cylinder engines, the crankcases having common mounting structure to which the cylinder members may be attached. Thus, the manner in which the cylinder members are attached to the crankcases is the same for each of the different types of crankcases. Two different types of cylinder members are provided, one having a side valve or “L-head” valve train, and the other having an overhead cam (“OHV”) valve train. The cylinder members are therefore modular components which may be selectively used in a variety of different types of engines.
Abstract:
A lead frame disposed within the confines of an engine cover, having an insulating portion and an electrically conducting portion. The conducting portion has at least one electrically conducting interconnect. Both the insulating portion and the electrically conducting portion form an integral piece for retaining and accurately positioning devices within an internal combustion engine. The lead frame includes a plurality of retaining elements for retaining or positioning of at least some of the devices; and an electrical connector member extending outside the confines of the internal combustion engine, the electrical connector member having a plurality of electrically conducting terminals in electrical communication with at least some of the devices within the internal combustion engine by means of the at least one electrically conducting interconnect, whereby at least some of the devices are retained and accurately positioned within the internal combustion engine.
Abstract:
An air-cooled internal combustion engine includes a cylinder block having a plurality of cylinder bores disposed in parallel to each other, a cylinder head secured to an upper portion of the cylinder block, a crankshaft, two camshafts disposed in a parallel, juxtaposed relationship to each other so as to extend perpendicularly to a forward and backward direction of a vehicle on which the engine is mounted at an upper portion of said cylinder head and positioned on front and rear sides of the engine relative to each other, and a camshaft driving mechanism for transmitting rotational driving force of the crankshaft to the camshafts. A cooling space into which wind can be introduced is formed below that one of the camshafts which is positioned on the front side of the engine. The entire cylinder head is thus cooled efficiently, including portions corresponding to the cylinders disposed at intermediate positions of the engine.