Abstract:
A variable valve device for an engine, may include a camshaft; a movable cam device fitted over the camshaft to be slidable in an axial direction of the camshaft, and configured such that cams with at least two different cam profiles and a guide protruding portion are disposed along the axial direction of the camshaft; at least one shaft groove linearly processed to have a predetermined cross-sectional shape in an external circumferential surface of the camshaft along the axial direction thereof; a cam groove provided in an internal circumferential surface of the movable cam device to communicate with the shaft groove; and an insertion member inserted into a communication space defined by the shaft groove and the cam groove such that a rotational displacement of the camshaft is transmitted to the movable cam device.
Abstract:
A valve train may include a camshaft having first and second slide guides, first and second cams mounted axially adjacent in torque-proof manners on the camshaft, and a cam follower adjustable between a first position, in which the cam follower is drivingly connected with the first cam, and a second position, in which the cam follower is drivingly connected with the second cam. The valve train may also include an adjustment arrangement having adjustable mechanical first and second engagement elements for axially adjusting the cam follower between first and second positions. Each engagement element may be adjustable between basic positions, in which no contact exists with a respective one of the slide guides, and switching positions, in which the respective engagement element cooperates with the slide guide. Each engagement element may have a spring that prestresses it into the switching position. The valve train may further include an arresting device and an actuator for each engagement element, wherein the arresting device, when in a locked position, holds the associated engagement element in the basic position, and the actuator releases the arresting device
Abstract:
A continuously variable valve timing apparatus may include a camshaft, a plurality of wheels mounted to the camshaft, of which a wheel key is formed thereto respectively, a plurality of cam portions of which a cam and a cam key are formed thereto respectively, of which the camshaft is inserted thereto, of which relative phase angle with respect to the camshaft is variable, a plurality of inner brackets connected with the each wheel key and the each cam key, a plurality of a slider housings of which the each inner bracket is rotatably inserted thereto respectively, and rotatably configured around a hinge hole formed an upper side of a cam cap and a control portion selectively moving the slider housings to change relative position of a rotation center of the inner brackets.
Abstract:
In a cam housing structure for a three-dimensional cam including: plural intake side supporting parts rotatably supporting an intake side camshaft from above; and plural exhaust side supporting parts rotatably supporting an exhaust side camshaft from above at an upper part of a cylinder head, any one of the supporting parts of the intake side supporting parts or the exhaust side supporting parts is coupled to two or more pieces of the other supporting parts via reinforcing members.
Abstract:
An overhead-camshaft internal combustion engine is disclosed, in which the fuel pumps are arranged to use efficiently the space within a cylinder head assembly of the engine. The cylinder head assembly includes a cylinder head block, and the engine comprises a camshaft rotatable about a camshaft axis and having a plurality of inlet and exhaust cams for actuating associated inlet and exhaust valves of the engine, and at least one fuel pump comprising a unit pump assembly driven directly by a respective pump cam provided on the camshaft. The engine further comprises a plurality of rocker arms driven by the inlet and exhaust cams and arranged to actuate the inlet and exhaust valves. Each rocker arm is pivotable about a rocker arm axis which is substantially parallel to the camshaft axis. The or each pump assembly is mounted between the rocker arm axis and the cylinder head block.
Abstract:
A continuous variable valve duration apparatus may vary an opening duration of a valve. The continuous variable valve duration apparatus may include a camshaft in which a camshaft slot is formed, a cam portion of which a cam and a cam slot are formed thereto and of which a rotation center is identical to a rotation center of the camshaft and the cam portion of which a phase angle to the cam shaft is variable, and a duration control portion which varies the phase angle between the camshaft slot and the cam slot.
Abstract:
A desmodromic valve system which provides direct bidirectional displacement of a valve stem of an internal combustion engine without the aid of a rocker arm, utilizing a semirigid basket operating in conjunction with a plurality of cams for each valve. The basket is disposed about the camshaft of the engine and secured to the valve stem by an integral retainer on a bottom portion of the basket, and is constrained to motion along the valve stem axis. The basket has a pair of downwardly oriented cam followers in the upper portion thereof, spaced apart from the valve stem axis. A central cam and a parallel pair of side cams are fixedly mounted on the camshaft so as to rotate therewith, the cams substantially surrounded by the basket and cooperating therewith to provide reciprocating valve action with positive bidirectional drive. The central cam is aligned with the valve stem axis, and the side cams are spaced apart from the valve stem axis, parallel to the central cam and respectively aligned with the cam followers. During a first part of a valve cycle, the central cam pushes the valve stem down so as to positively open the associated valve, and the valve stem pulls said basket down with it via the retainer. During a second part of the valve cycle, the side cams push the basket up via their respective cam followers and thereby cause the basket to pull the valve stem so as to positively close the valve.
Abstract:
A roller bearing includes an outer ring formed by connecting a plurality of arc-shaped outer ring members in a circumferential direction and a plurality of rollers arranged along an inner diameter surface of the outer ring. A slope surface (22i) is provided at one or each circumferential end on an inner diameter surface of the outer ring member (22a), and a contour line of the slope surface (22i) is along a direction perpendicular to a revolution direction of the roller.
Abstract:
An engine assembly may define first and second combustion chamber and may include a camshaft having a first lobe region engaged with the first valve arrangement and a second lobe region engaged with the second valve arrangement and rotatable relative to the first lobe region. The cam phaser may be coupled to the camshaft and may include a first member and a second member rotatable relative to the first member. The first lobe region may be fixed for rotation with the first member and the second lobe region may be fixed for rotation with the second member to vary valve timing for the second combustion chamber independently from the valve timing of the first combustion chamber.
Abstract:
Featured is a rollerized camshaft support to rotatably support a camshaft of a Type I valvetrain, the camshaft having at least one rotating surface. Such a rollerized camshaft support includes at least one rollerized bearing and at least one bearing support for each of the rollerized bearings, where each bearing support includes a bearing upper support element and bearing lower support element. Each rollerized bearing includes an inner raceway; an outer raceway and a plurality of rolling elements disposed between the inner and outer raceways and extending widthwise across the raceways. The bearing upper support element and bearing lower support element are configured so as to receive there between a rollerized bearing. Also, the bearing lower support element is configured and arranged so to complement a portion of a configuration of the Type I valve train.