A compression release mechanism including a camshaft, a cam provided on the camshaft and protruding outward in a radial direction of the camshaft, a lever, of which a portion is disposed in the camshaft, a support shaft supporting the lever such that the lever is swingable between a first position and a second position relative to the camshaft, and a spring attached to the camshaft, to urge the lever toward the first position. The lever includes a cam portion configured to protrude out from the camshaft with the lever at the first position, a centrifugal weight for moving the lever toward the second position in accordance with rotation of the camshaft, and an abutment portion configured to be in abutment with an inner peripheral surface of the camshaft with the lever at the first position, and be located away from the inner peripheral surface with the lever at the second position.

Intake holes at the opposite ends are opened and closed by first intake valves. The middle intake hole is opened and closed by a second intake valve. A control device includes an intake variable valve device. First branch channels are connected to the intake holes and produce a normal tumble flow. A second branch channel is configured such that the flow rate of intake air passing through the middle intake hole is relatively greater on the side closer to the outer periphery of the combustion chamber. Where increasing the flow coefficient is given a higher priority, a three-valve drive mode is selected. Where the strength of the normal tumble flow is enhanced, a two-valve drive mode is selected. Where production of the normal tumble flow is reduced, a one-valve drive mode is selected.

Methods and systems are provided for actuating an advanced cam profile switch (CPS) assembly. In one example, a system may include a first cylinder and a second cylinder of the CPS assembly that may be independently coupleable to a valve stem via two separate locking mechanisms. A first cam may be selectively engage with the first cylinder and the valve stem and a second cam may be selectively engaged with the second cylinder and the valve stem.

The invention pertains to gas exchange in internal combustion engines using low to zero-emission fuels. The combustion engine has the ability to regulate the quantity of air/fuel mixture in the cylinder using one or more exhaust valve(s) (2) that can have adjustable opening times in order to control the gas exchange in the cylinder so that exhaust and alternatively also air can be expelled into the exhaust system. By reducing the quantity of air and thus the quantity of fuel for each cycle, that combined with reduced compression pressure means that engines can operate with a higher expansion ratio by leaving the exhaust valve(s) (2) open through a part of the compression stroke to reduce the amount of air to the combustion and reduce compression and then pressure rise before combustion. Air volume and gas exchange are regulated by compressor(s) (5) as well as opening and closing of exhaust valve(s) (2) with the exhaust valve control (4); alternatively, also intake valves for 4-stroke engines.

A valve train may include a camshaft, a cam follower, and first and second cams mounted axially adjacent in a torque-proof manner on the camshaft. The valve train may also include an adjustment arrangement having adjustable first and second mechanical engagement elements, which may each cooperate with at least one slide guide arranged on the camshaft. The valve train may further include a control shaft or control slide forming a stop for the first and second engagement elements and adjusting the first and second engagement elements into respective switching positions. The cam follower may be drivingly connected with the first and second cams in first and second positions, respectively. The first and second engagement elements may each be adjustable between respective basic positions, in which no contact exists with the associated slide guide, and the respective switching positions, in which the respective engagement element cooperates with the associated slide guide.

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

A continuous variable valve duration 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 slider housings of which the each inner bracket is rotatably inserted thereto, and movable up and down direction of an engine, a control portion selectively moving the slider housings to adjust relative position of a rotation center of the inner brackets and a guider guiding movement of the sliding housings.

The present disclosure provides a camshaft phase adjuster, including: a stator provided with a plurality of hydraulic chambers; a rotor rotatably disposed in the stator and provided with a basic body and a plurality of blades fixed to the basic body, the basic body has a first end surface and the second end surface which face opposite directions along an axial direction, the plurality of blades are arranged in intervals along the circumferential direction and divide the hydraulic chambers into first pressure chambers and second pressure chambers, respectively; wherein the basic body is provided with a plurality of first oil holes and a plurality of second oil holes which are communicated with the first pressure chambers and the second pressure chambers, respectively, the second oil hole is provided with at least two oil sub-holes, a first oil sub-hole extends along a radial direction of the basic body and is located on a same plane, with the first oil hole, perpendicular to a central axis of the rotor, the first oil sub-hole communicates with the second pressure chamber, and the second oil sub-hole penetrates through the first end surface along an axial direction of the basic body. Accordingly, technical solution of the present disclosure solves the problems of large in axial dimension and great in mass of existing camshaft phase adjusters.

A continuous variable valve duration apparatus may include a camshaft, a first and second cam portions, first and inside brackets transmitting rotation of the camshaft to the first and second cam portions respectively, a slider housing of which the first and second inside brackets are rotatably inserted thereto, cam caps of which each cam cap engaging portion is rotatably connected thereto, a connecting bracket connecting the cam caps and of which a guide opening for the guide protruded portion to be inserted thereto for guiding movement of the slider housing is formed thereto, a slider pin rotatably inserted into the first sliding opening and slidably inserted into the camshaft, a cam pin of which a cam opening for the cam to be slidably inserted thereto is formed and rotatably inserted into the second sliding opening and a controller selectively changing a position of the slider housing.

A continuous variable valve duration apparatus may include a camshaft, a cam device, of which the camshaft is inserted thereto, of which a phase angle with respect to the camshaft is variable, and the cam device on which a cam key is formed, an inside bracket transmitting rotation of the camshaft to the cam device and on which a first slide opening and a second sliding opening are formed respectively, a slider housing in which the inside bracket is rotatably inserted and of which relative position with respect to the camshaft is variable, a controller selectively changing the relative position of the slider housing, a cam pin of which a cam key opening for the cam key to be slidably inserted thereto is formed and slidably inserted into the second sliding opening and a slider pin rotatably inserted into the first sliding opening and slidably inserted into the camshaft.