Abstract:
A valve timing controller has a case which defines a fluid chamber therein. A magnetic viscosity fluid is enclosed in the fluid chamber. The magnetic viscosity fluid including magnetic particles and its viscosity varies according to a magnetic field applied thereto. A coil and a control circuit applies magnetic field to the magnetic viscosity fluid to variably control a viscosity thereof. A brake rotor is rotatably accommodated in the fluid chamber and receives a brake torque from the magnetic viscosity fluid according to the viscosity thereof. A phase adjusting mechanism is connected to the brake rotor for adjusting a relative rotational phase between the crankshaft and the camshaft according to the brake torque. When it is estimated that the engine will be started, the coil is energized to generated heat in the magnetic viscosity fluid.
Abstract:
An electric power supply driver executes duty control of turning on and off of a selected switching element to supply electric power to a corresponding stator coil in a case where an actual rotational direction and a target rotational direction of a motor shaft coincide with each other. Furthermore, the driver sets an on-duty ratio of the selected switching element below a lower limit value, which is at least required to rotate the motor shaft through the power supply to each corresponding stator coil in a case where the actual rotational direction and the target rotational direction do not coincide with each other.
Abstract:
A valve timing controller has the drive circuit which performs a feedback control of the energization to the electric motor based on the target rotation speed and the actual rotation speed of the electric motor, and rotates the electric motor to the target rotation direction. An invalid switch part of the drive circuit suspends the feedback control at the time of change of the target rotation direction.
Abstract:
In a procedure to operate an internal combustion engine with an electrohydraulic valve control which comprises electrically activated oil control valves for hydraulic actuators for the actuation of charge-cycle valves, a motor control unit as well as an output stage unit, which is connected to the motor control unit via a data link, at least a limited operation of the internal combustion engine is made possible during a breakdown of the data bus between the motor control unit and the output stage unit, in that the output stage unit is transferred into an autonomous mode of operation during a breakdown of the data link to the motor control unit.
Abstract:
A closed-loop control for a cam phase adjustment mechanism includes gain terms that are adaptively adjusted to optimize the rate of response of the control to changes in the desired cam phase. The rate of response of the cam phase adjustment mechanism is sampled under specified operating conditions or during certain repeated engine events that involve a change in the desired cam phase, and the deviation of the measured rate of response from the nominal rate of response is determined and used to adjust the closed-loop control gains for restoring the nominal response.
Abstract:
A requested volume flow ratio calculated based on a requested torque, an amount of two times a spit-back gas amount at the valve overlap time calculated based on a requested residual gas rate, and a spit-back gas amount of the time when an intake valve is closed are added together, to set a requested valve passing gas amount of the intake valve, thereby determining a target operating characteristic of the intake valve based on the requested valve passing gas amount.
Abstract:
A cam 13 formed so that cam height and a cam operation angle continuously change, and constituted to be rotated integrally with a camshaft 11 and relatively movable in an axial direction thereof, a valve lifter 20 pressed by a cam surface of the cam 13 to advance and retreat a valve, and an accelerator shaft unit 40 for moving the cam 13 in the axial direction of the camshaft 11 are included. The accelerator shaft unit 40 includes an accelerator shaft 41 placed to be capable of reciprocating in the axial direction of the camshaft, and an accelerator fork 42 supported at the accelerator shaft 41 and engaging with the cam 13, and has an adjust mechanism 70 for finely adjusting a relative position in an axial direction of the accelerator fork 42 with respect to the accelerator shaft 41.
Abstract:
The invention relates to a camshaft adjuster (1) for adjusting and fixing the relative position of the angle of rotation of a camshaft (8) in relation to a crankshaft of a reciprocating piston internal combustion engine. The adjusting device comprises a high transmission and friction-reduced adjusting gear mechanism (2), comprising a drive shaft which is rotationally fixed to the crankshaft, a driven shaft which is rotationally fixed to the camshaft (8) and an adjusting shaft (9) which is connected to an adjusting motor shaft (10) of an adjusting motor. A camshaft adjuster (1), which is economical to run, can be produced such that the adjusting gear mechanism (2) and the adjusting motor (3) are embodied as separate units and are connected together by a rotational backlash-free, disengaging coupling (4).
Abstract:
In an internal combustion engine, which is provided with a variable valve mechanism that varies an open/close characteristic of an intake valve, a target open/close characteristic of the intake valve is determined. Simultaneously, a control speed at a time when the intake valve is controlled to have the target open/close characteristic is determined. As a result, the variable valve mechanism is controlled according to the target open/close characteristic and the control speed.
Abstract:
In an engine provided with a variable valve event and lift mechanism that varies a valve lift and a valve operating angle of an intake valve, a pressure of fuel supplied to a fuel injection valve is controlled according to an opening period of the intake valve, which is varied according to the valve operating angle and an engine rotation speed.