An intake device of an internal combustion engine, includes: a plurality of intake ports which have outer walls and partition walls and are adjacent to each other via the partition walls; a valve body which is provided in each of the intake ports, and switches a flow path of the intake port by rotation around a rotation shaft; a holding member which is installed on each of the outer walls and the partition walls; and a rolling bearing which is mounted on at least one of the holding members, and supports the valve body to be freely rotatable, wherein the holding member includes a wall surface between the rolling bearing and the valve body in a direction in which the rotation shaft extends.

A hydrogen intake assembly for a hydrogen internal combustion engine characterized in that the hydrogen intake assembly includes at least one air intake manifold comprising an air intake pipe comprising at least one air inlet and air outlets, air intake runners comprising air inlets and air outlets, a spacer having a wall defining an inner chamber receiving a mixture of air, water and hydrogen and comprising air inlets and mixture outlets delivering said mixture, a water rail comprising at least one water inlet and water outlets, said water outlets being embedded in the wall of the spacer and a hydrogen rail comprising at least a hydrogen inlet and hydrogen outlets.

A sleeve structure comprises a plurality of sleeve main bodies fitted respectively into intake ports of a cylinder head of a multi-cylinder internal combustion engine and a shared base provided on one end of the plurality of sleeve main bodies. By fixing this sleeve structure to the cylinder head, an amount of labor involved in a fixing operation for fixing sleeves to a cylinder head is reduced.

A two-stroke engine (1) is disclosed comprising a cylinder (2), a piston (3) arranged to reciprocate in the cylinder (2), a crankcase (5), a fuel injector (7) configured to inject fuel into the crankcase (5), an air inlet (9) connected to the crankcase (5), and a stratified scavenging intake (11) connected to the cylinder (2). The engine (1) comprises a throttle (13) configured to control the amount of air supplied to the air inlet (9) and to the stratified scavenging intake (11). The present disclosure further relates to handheld power tool (50) comprising an engine (1).

Methods and systems are provided for modified intake runners including ribs in the direction of airflow. In one example, a system may include an intake manifold adapted to couple to an intake port via an intake runner. Internal to the intake runner, a plurality of negative ribs may be arranged along a direction of air flow on a façade of an inner portion.

An engine intake bypass system includes: an inlet pipe that supplies air, which passes through a throttle valve, to an intake manifold via a supercharging device along a first path, and directly supplies the air having passed through the throttle valve the intake manifold after bypassing the supercharging device along a second path; a bypass duct disposed in the second path to receive the air from the inlet pipe and deliver the air to the intake manifold in parallel; and a bypass valve installed to interrupt the air supplied to the bypass duct.

An engine intake bypass system includes: an inlet pipe that supplies air, which passes through a throttle valve, to an intake manifold via a supercharging device along a first path, and directly supplies the air having passed through the throttle valve the intake manifold after bypassing the supercharging device along a second path; a bypass duct disposed in the second path to receive the air from the inlet pipe and deliver the air to the intake manifold in parallel; and a bypass valve installed to interrupt the air supplied to the bypass duct.

An air intake circuit for a heat engine is intended to be positioned between an air compression element and at least an upper portion of a hollow combustion chamber in a cylinder head of the engine. The air intake circuit includes the cylinder head, an air intake manifold, and at least one air intake duct. The circuit also includes at least one concave receptacle turned towards the outside of the engine, housed in a cavity of the cylinder head, and connected to a tubular element pushed into the at least one air intake duct.

The disclosure relates to an air inlet system for an internal combustion engine. The air inlet system has a cylinder head having an inlet channel for introducing inlet air into a combustion chamber of the internal combustion engine. The air inlet system has an air supply pipe piece, which is connected to the cylinder head and which at least partially forms an air supply channel, which opens in the inlet channel. The air inlet system additionally has thermal insulation, which is arranged in the air supply channel in order to reduce a heat transfer to the inlet air which flows in the air supply channel.

The present disclosure provides air intake ports and/or intake manifolds having an altered configuration to improve the efficiency of the air intake ports, intake manifolds, and by extension, the engine.