A multi-cylinder internal combustion engine having an intake manifold equipped with a variable venturi type carburetor. A secondary throttle valve is provided for each cylinder. Each of the secondary throttle valves is arranged in the respective manifold branch. An auxiliary intake passage is branched off from the collecting portion of the intake manifold and connected to a distribution channel formed in the cylinder head. Each of the intake ports is connected to the distribution channel via a corresponding channel branch which opens into the intake port at a position near the intake valve. A primary throttle valve is arranged in the auxiliary intake passage and opened in accordance with an increase in level of the load of an engine. The secondary throttle valves are opened after the opening degree of the primary throttle valve is increased beyond a predetermined opening degree.

Intake system of a multi-cylinder internal combustion engine

A concave surface (32) forms a section of the inner wall (30) of an inlet air passage (22) in the cylinder head of an internal combustion engine with the concave surface (32) facing towards the outer wall (28) of the passage (22). The inlet passage (22) leads to a valve (14) past which air is introduced into a cylinder (12) of the engine.

Inlet air passage for an engine

In an internal combustion engine which is provided with a throttle valve of the type which, when slightly opened, provides a flow of intake gases which is biased towards one particular side of the intake passage, and which is provided with a helical type inlet port which has a helical surface leading to the combustion chamber which imparts swirl to inlet gases, a vane is provided, which particularly directs gases passing near that one particular side of the intake passage towards the start of the helical surface, whereby good swirl and turbulence are generated in the power cylinder, especially during low and medium load operation of the engine.

Vane in the inlet passage of an internal combustion engine

A vortex fuel air mixer is positioned between the air throttle and the intake manifold of an engine. Part of the expansion flow velocity past the air throttle flows tangentially into the vortex chamber of the mixer, providing angular momentum which drives the flow into a vortical pattern. The flow streamlines within the vortical flow form into a generally irrotational flow pattern which swirls from the outside wall of the vortex chamber inwardly to a central vortex chamber outlet. This outlet feeds the engine intake manifold. Centrifugal forces in the swirling flow fling fuel droplets to the outside wall of the vortex chamber (in the manner of a cyclone scrubber). This liquid fuel must evaporate in order to leave the vortex chamber. The interaction of the evaporation, flow structure and turbulence relations inside the vortex chamber produces an essentially homogeneous mixture at the vortex chamber outlet. Fuel evaporation time in the vortex chamber is quite short, so that the device exhibits excellent transient response.

Vortex fuel air mixer

An internal combustion engine comprises a cylinder and an intake passageway opening into the cylinder. In order to secure sufficiently high volumetric efficiency at high speed under high load operating conditions, the intake passageway is so configured as to pass therethrough a sufficient volume required for the combustible charge to be drawn into the cylinder per unit time. The intake passageway is provided with swirl means for causing the combustible charge passing through the intake passageway to swirl in the cylinder. The swirl means comprises at least one flow restrictor means so arranged as to urge the combustible charge to enter into the cylinder in a tangent direction to the cylinder wall. Control means is provided whereby the flow restrictor means reduces effective flow area thereof at low speed under light load operating conditions, thus securing strong swirl, and the flow restrictor means increase effective flow area thereof at high speed under high load operating conditions, thus securing high volumetric efficiency.

Internal combustion engine with intake arrangement to produce swirl in combustion chamber

Disclosed is an internal combustion engine, and in particular a diesel engine, wherein the fuel-air mixture provided to the cylinder is improved by splitting the airstream directed to the cylinder into at least two partial streams and thereafter reuniting the partial streams at an angle relative to one another whereby turbulence is provided to provide a more uniform mixture of air and fuel.

Method for the improvement of mixture formation in the cylinder of an internal combustion engine and internal combustion engine operated in accordance with this method

List Hans Prof Dipl Ing Dr Dr

Papers

Method for the improvement of mixture formation in the cylinder of an internal combustion engine and internal combustion engine operated in accordance with this method

Verfahren zur verbesserung der gemischbildung im zylinder einer brennkraftmaschine und nach diesem verfahren betriebene brennkraftmaschine