Abstract:
A variable valve operating apparatus includes a drive camshaft that is rotationally driven by the rotational force of the crankshaft, and a driven cam lobe that is rotatably supported by the drive camshaft. The variable valve operating apparatus further includes a guide member that has a raceway surface formed so as to surround the drive camshaft. The variable valve operating apparatus further includes a link mechanism that is connected to each of the drive camshaft and the driven cam lobe and has a control roller which is in contact with the raceway surface. The variable valve operating apparatus further includes a link plate and holding rollers that maintain contact between the raceway surface and the control roller while the drive camshaft makes one rotation. The variable valve operating apparatus further includes an actuator that drives the guide member.
Abstract:
Provided is a valve timing adjustment system having improved control for achieving a target rotational phase. The valve timing adjustment system includes: a displacement mechanism unit that displaces a rotational phase of a camshaft relative to a crankshaft of an internal combustion engine; a locking mechanism unit that locks the rotational phase at an intermediate locked phase positioned within a displacement range of the rotational phase; a hydraulic pathway that hydraulically drives the displacement mechanism unit and the locking mechanism unit; and a control unit including a control system that controls operations of the hydraulic control valve. The control unit changes a temporal responsiveness of the control system based on a displacement force that displaces the rotational phase.
Abstract:
A camshaft adjuster (1), which has a cover element (4), which has at least one deformation zone (7), which, when the cover element (4) is assembled with the input element (2) or the output element (3), is deformed in such a way that a preloading force acts, pressing the cover element (4) and the input element (2) or output element (3) against one another.
Abstract:
In a valve timing control apparatus configured to enable rotary motion of a vane rotor relative to a sprocket in a phase-retard direction or in a phase-advance direction by controlling hydraulic-pressure supply-and-exhaust for each of phase-advance hydraulic chambers and hydraulic-pressure supply-and-exhaust for each of phase-retard hydraulic chambers, first and second lock pins are located in a large-diameter rotor portion rather than a small-diameter rotor portion. The rotary motion of the vane rotor relative to the sprocket from an intermediate lock position between a maximum phase-advance position and a maximum phase-retard position is restricted by engagement of the first lock pin with a first lock hole and by engagement of the second lock pin with a second lock hole. The vane rotor is held at the maximum phase-retard position by engagement of the first lock pin with the second lock hole.
Abstract:
A centric phase of an operating angle of an engine valve is detected on the basis of an interval between a reference rotational position of a crankshaft and a reference rotational position of a camshaft, and on the other hand, the centric phase is detected each predetermined time, and a Variable valve Timing Control mechanism is feedback-controlled on the basis of a value which has been updated more recently between both detected results.
Abstract:
In a direction-injection engine incorporating a turbocharger, fuel combustion is improved to enhance fuel economy within the high-load range of engine torque, and furthermore to control occurrence of smoke in the range of great load within the lean-burn range. Scavenging acceleration control is conducted to scavenge the exhaust gases in the combustion chamber by using at least one of the intake pipe pressure, the combustion chamber pressure, and the exhaust pipe pressure, and the fuel is injected twice during the intake stroke and the compression stroke.
Abstract:
A hydraulic actuator is provided with a housing with an oil compartment formed therein; a power output shaft rotatably supported on the housing and extending out from an interior of the oil compartment to an exterior of the housing; a vane radially extending out from the power output shaft and maintained in contact with an inner wall of the oil compartment, whereby the vane divides the oil compartment into a first oil compartment and a second oil compartment; a first hydraulic pressure passage communicating the first oil compartment and a hydraulic pressure source with each other; a second hydraulic pressure passage communicating the second oil compartment and the hydraulic pressure source with each other; and an oil control valve regulating at least one of a first hydraulic pressure to be supplied to the first oil compartment through the first hydraulic pressure passage and a second hydraulic pressure to be supplied to the second oil compartment through the second hydraulic pressure passage. The power output shaft is specified in its rotated position by the first and second hydraulic pressures acting on the vane. A variable valve driving mechanism making use of the hydraulic actuator is also disclosed.
Abstract:
A variable phase valve timing assembly for an internal combustion engine. A camshaft driven by a rotating crankshaft of the invention actuates an intermediate member such as a pivotally mounted lever a bucket tappet a first portion of which bears against a cam supported by the camshaft and a second portion of which bears against a valve of the engine such that rotation of the camshaft displaces the intermediate member and valve in a cyclical manner. The camshaft is displaceable relative to the intermediate member along a predetermined path, and means are provided for displacing the camshaft in dependence upon a control input, for example engine speed. The geometry of the predetermined path and of the first portion of the intermediate member are such that movement of the camshaft alters the phase of displacements of the valve relative to rotation of the engine.
Abstract:
A phase changing mechanism is disclosed which is applicable to a valve gear of a dual overhead camshaft internal combustion engine. The mechanism comprises a driving shaft, a cam rotatable relative to the driving shaft, a drive member fixed to the driving shaft, a driven member integral with the cam, a support, an intermediate member rotatablly supported in an eccentric circular cam integral with the support, a first coupling coupling the drive member with the intermediate member at a first position spaced from an axis of the driving shaft, and a second coupling coupling the driven member with the intermediate member at a second position angularly spaced from the first position with respect to the shaft axis. The first coupling has a movable connection with the intermediate member to permit variation in a distance of the first position from an axis of rotation of the intermediate member during operation. The second coupling has a movable connection with the intermediate member to permit variation in a distance of the second position from the axis of rotation of the intermediate member during operation. The support is rotatably supported by at least one of the drive and driven members.
Abstract:
An improved control device for intake and/or exhaust valves of an internal combustion engine includes a small circumference portion defined in a drive shaft at a location corresponding to that of an annular member which is eccentrically displaced for changing a rotational phase of the cams. According to this a degree of displacement of the annular member may be increased and control the cams, and thereby the engine valves, may be enhanced. Further, the cam lobe of each cam is formed such that side portions thereof are asymmetrical with respect to a center line of the cam for favorably affecting valve opening and closing timings. In addition, an improved lubricating arrangement for enhancing smooth operation and improved engine performance.