Abstract:
A variable valve apparatus of an internal combustion engine includes a first rocker arm that contacts a cam, a low lift cam provided coaxially with the cam, and a second rocker arm capable of contacting the low lift cam. The apparatus also includes a switching mechanism capable of connecting the first rocker arm and the second rocker arm to each other through pins, valves that open by being pressed by the second rocker arms via hydraulic lash adjusters arranged in the second rocker arms, and an oil supply path formed inside the second rocker arms that supplies oil to the hydraulic lash adjusters. A radius of a base circle of the low lift cam is smaller than a radius of a base circle of the cam.
Abstract:
Provided is a control apparatus for an internal combustion engine that can suppress deterioration of a catalyst that is ascribable to a control delay of a variable valve operating apparatus when transitioning to a valve stopped state accompanying a fuel-cut operation, or when transitioning from the valve stopped state to a combustion limit operating state. An intake variable valve operating apparatus capable of changing the operating state of an intake valve to a valve stopped state by continuously changing a lift amount and working angle of the intake valve is included. When the temperature of a catalyst is equal to or greater than a predetermined temperature, fuel injection is executed to supply fuel into an exhaust passage during a period in which the operating state of the intake valve transitions to the valve stopped state, during a period in which a fuel-cut operation is executed in the valve stopped state, or during a period in which the operating state of the intake valve transitions from the valve stopped state to a return limit operating state.
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:
A six-cylinder engine includes a stop-cylinder-setting section. The stop-cylinder-setting section sets to-be-stopped cylinders such that cylinders operated in a four-cylinder operation mode (two cylinders stopped) are stopped in a two-cylinder operation mode (four cylinders stopped), and the cylinders operated in the two-cylinder operation mode are stopped in the four-cylinder operation mode. The stop-cylinder-setting section stops operations of intake valves corresponding to stopped cylinders in each operation mode.
Abstract:
An object of the present invention is to decrease the size of rocker arms and reduce friction in a variable valve apparatus of an internal combustion engine having a hydraulic lash adjuster arranged in rocker arms. A variable valve apparatus of an internal combustion engine of the present invention includes a first rocker arm that contacts a cam, a zero lift cam (low lift cam) provided coaxially with the cam, second rocker arms capable of contacting the zero lift cam, a switching mechanism capable of connecting the first rocker arm and the second rocker arm to each other through a pin, valves that open by being pressed by the second rocker arms via hydraulic lash adjusters arranged in the second rocker arms, and an oil supply path formed inside the second rocker arms that supplies oil to the hydraulic lash adjusters. A radius of a base circle of the zero lift cam is smaller than a radius of a base circle of the cam.
Abstract:
The present invention makes it possible to favorably change valve-opening characteristics of a valve using a simplified configuration without leading to an increase in the number of components and also without causing an increase of friction due to sliding, in a valve operating apparatus for an internal combustion engine in which the valve-opening characteristics of the valve are variable. A changeover mechanism for switching the connection/disconnection of rocker arms disposed between cams and a valve is provided. When a slide pin reaches a displacement end in the retreating direction of changeover pin, the biasing force of a return spring acting on changeover pins is received by an engaging part between a notch part provided in the slide pin and a lock pin in a state separated from a camshaft.
Abstract:
A lost motion spring is disposed to contact at one end an oscillating member interposed between a cam and a valve for synchronizing the oscillating of the valve with the rotation of the cam. The lost motion spring impels the oscillating member toward the cam. A spring support shaft is provided for supporting a second portion of the lost motion spring. A spring position adjustment mechanism is provided for adjusting the mounting position of the lost motion spring relative to the spring support shaft.
Abstract:
A motor 30 or the like is used to drive a camshaft 22 or the like having a cam 18 or the like to push a valve 12 biased in the closing direction of the valve by a valve spring 17. Between the cam 18 or the like and the valve 12 is present a valve lifter 16 that abuts the cam 18 or the like. The valve lifter 16 includes a top face 16a formed so that when viewed from the axial direction of the camshaft 22 or the like, a tangential direction to the nose tip 18c of the cam 18 or the like inclines with respect to the direction perpendicular to the axial line of a valve stem 14.
Abstract:
A variable valve operating device that makes it possible to reduce the loss in driving force transmission from a camshaft to a valve during a valve lift is provided. The rotary motion of a drive cam is transmitted to a swing member via intermediate rollers. A coupling member couples the intermediate rollers, to a swing fulcrum that is fastened to a control shaft. The swing fulcrum is positioned eccentrically to the center of the control shaft. Further, when the control shaft is positioned at a predetermined rotation position, the swing fulcrum is positioned so that the control shaft is placed between the swing fulcrum and the intermediate rollers. Preferably, the swing fulcrum, the control shaft, and the intermediate rollers are aligned.
Abstract:
Disclosed is a variable valve mechanism for an internal combustion engine. The variable valve mechanism accurately adjusts the valve operating angle although its structure is simple. The variable valve mechanism includes a control pin 48, which is inserted into a pin insertion hole 38 in a control shaft 16; a bearing hole 44, which is formed in a control member 26; and an adjustment pin 50, which is rotatably supported by the bearing hole 44. The adjustment pin 50 comes into surface contact with the control pin 48 to inhibit the control member 26 from rotating relative to the control shaft 16. The valve operating angle is adjusted by replacing the adjustment pin 50 with another having a different dimension B. Such adjustment pin replacement changes the distance A between the center line of the bearing hole 44 and the center line of the control pin 48, thereby changing the relative angle θ between the control shaft 16 and control member 26. When the adjustment pin 50 rotates within the bearing hole 44, the surface contact between the adjustment pin 50 and control pin 48 is maintained irrespective of the magnitude of the relative angle θ.