Abstract:
The invention relates to a variable valve system for an internal combustion engine including an electric motor that can be rotated in any one of a normal rotation direction and a reverse rotation direction; a first cam that is driven by the electric motor; a second cam that has a same shape as the first cam, that is driven by the electric motor, and that differs from the first cam in a rotation phase; a first valve that is opened and closed by the first cam; a second valve that is opened and closed by the second cam; and a control unit that controls rotation of the electric motor. Each of the first cam and the second cam is symmetric with respect to a straight line passing a cam center and a cam nose.
Abstract:
The rotary motion of a camshaft is transmitted from a first drive cam to a slide surface of a swing cam arm via intermediate members so that the swing cam arm lifts a valve. In this instance, the operating characteristic of the valve changes when the rotation position of a control shaft changes to change the positions of the intermediate members on the slide surface. When the operating characteristic control mode for the valve is to be changed from variable control to fixed control, coupling means couples the swing cam arm and input arm, thereby causing a second drive cam to swing the swing cam arm. The setting for the lift amount of the valve that is obtained when the second drive cam swings the swing cam arm is not smaller than a maximum lift amount setting for a situation where the first drive cam swings the swing cam arm.
Abstract:
A variable valve operating device is provided that allows an ideal valve timing-lift characteristic to be realized by associating a change in a valve timing with a change in a valve lift amount. A rotation motion of a drive cam is transmitted to a slide surface of a swing member via an intermediate member. Positions of the intermediate member on the slide surface are varied in association with the rotation of a control shaft by an interlock mechanism. The slide surface is formed to be curved toward the drive cam so that the distance from the center of a camshaft increases toward the farthest point from the swing center of the swing member within the area which the intermediate member contacts from the nearest point from the swing center of the swing member within the area which the intermediate member contacts.
Abstract:
Intake camshafts 10, 14 for driving valve bodies 32 (intake valve) are positioned in right- and left-hand banks, respectively. A variable valve mechanism 30 is positioned in each of the right- and left-hand banks in such a manner as to form mirror-image symmetry. The variable valve mechanism 30 includes a control shaft 60 for controlling the operating angle of the valve body. The respective control shafts in the right- and left-hand banks are controlled in symmetrical directions. The right- and left-hand intake camshafts 10, 14 rotate in opposite directions and at a speed that is synchronized with the speed of a crankshaft.
Abstract:
A valve drive system comprises a power transmitting mechanism (13) that converts rotary motion of an electric motor (12) into opening and closing motion of an intake valve (3) provided in a cylinder (2) of an internal combustion engine (1) to transmit power from the electric motor (12) to the valve (3) via a cam (152); and a rotational angle restricting mechanism (16) that is provided in a motion transmission path that extends from the electric motor (12) to the cam (152) and restricts rotation of the cam (152) within a predetermined angular range that is set so that a piston (5) of the engine (1) and the intake valve (3) do not interfere with each other. The rotational angle restricting mechanism (16) comprises a flange (161) that rotates as a unit with a camshaft (151) and forms a slotted groove hole (161a) thereon; and a stopper pin (162) that is inserted into and retracted from the groove hole (161a).
Abstract:
An internal combustion engine valve mechanism including a rocker arm, which includes a bearing section and a rocker roller, and an HLA. The HLA has a pivot, which is to be inserted into the bearing section, and supports one end of the rocker arm. The pivot has a spherically curved surface, whereas the bearing section has a shell-shaped dent. A swing arm rotates in synchronism with camshaft rotation and gives roller pressure force to the rocker roller. The direction in which the swing arm presses the rocker roller shifts toward the HLA when the lift of a valve disc increases. An osculating circle is inclined by inclining the axis of the bearing section at an angle of α° relative to the axis of the HLA.
Abstract:
The present invention relates to a variable valve operating device and a valve opening amount adjustment method, and can accurately control the amount of in-cylinder air and the strength of a swirl flow. The variable valve operating device according to the present invention includes a valve mechanism that can select a dual valve variable control mode in which the valve opening amounts of a first valve and a second valve, which are of the same type and provided for the same cylinder, can be varied continuously or in multiple steps. A valve opening amount difference is provided when the valve opening amounts are minimized in the dual valve variable control mode so that the valve opening amount of the first valve is larger than that of the second valve. In addition, adjustments are made so that the minimum valve opening amount of the first valve does not vary from one cylinder to another.
Abstract:
There is provided a valve gear of an internal combustion engine converting a rotational motion of a motor into a linear motion by a cam, and driving an intake valve or an exhaust valve of a cylinder so as to be opened and closed based on the linear motion, a motor control apparatus which can actuate the motor in a rocking chive mode in which a rotating direction of the cam is changed during a lift of the valve. The motor control apparatus controls a motion of the motor such that the cam starts rotating before the valve starts lifting in the rocking drive mode.
Abstract:
There is provided a hybrid vehicle capable of attaining excellent acceleration response and reducing pumping loss. When an engine combustion stop demand is issued, the engine is associatively rotated by carrying out a fuel cut-off operation and controlling the speed of a generator to control the engine in such a way that the speed of the engine becomes a predetermined speed NE1. During the associative rotation, intake and exhaust valves are held at their fully closed positions.
Abstract:
This control device for an internal combustion engine includes a variable intake valve device and a variable exhaust valve device; and it performs fuel cut-off for a plurality of cylinders of the internal combustion engine. And it further includes: an intake valve control means which, when the fuel cut-off execution condition has come into effect, controls the variable intake valve device, so as to keep in a closed state the intake valve of a cylinder, for which an exhaust valve is not kept in a closed state; and an exhaust valve control means which, when the fuel cut-off execution condition has come into effect, controls the variable exhaust valve device, so as to keep in an open state an exhaust valve of at least a pair of cylinders, between which gases in the pair of cylinders come and go via an exhaust passage as the pistons operate.