DE2301066A1 - FOUR-STROKE PISTON ENGINE WITH EXTERNAL IGNITION - Google Patents

Description

Dr. Ing.

January 10, 1973 139/68

HONDA GIKEN KOGYO KABUSHIKI KAISHA

, Yaesu, Chuo-ku, Tokyo, Japan

Four-stroke piston internal combustion engine with spark ignition

The invention relates to internal combustion engines in which the or each cylinder has a main combustion chamber with inlet and outlet valves, and an auxiliary inlet valve arrangement is provided for regulating the inlet to an Ileberirauin which is equipped with a spark plug. The or each secondary combustion chamber communicates with the respective main chamber through a small opening known as a "torch nozzle". A rich fuel-air mixture is fed to the lift chamber through its auxiliary inlet valve arrangement, while a lean fuel-air mixture is fed to the main chamber through its inlet valve arrangement. In operation, the rich mixture can easily be found in the sub-combustion chamber

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through the spark plug ignite and enters the resulting Flammanfront through the torch nozzle to ignite the lean mixture in the main combustion chamber.

With such an internal combustion engine occur during a cold start and sometimes difficulties during normal operation because the fuel is in the rich mixture, that is fed to the adjoining room, has the tendency to condense on the walls of the inlet duct, which leads to loss of fuel and poor combustion.

A four-stroke piston internal combustion engine according to the invention with spark ignition has a main combustion chamber and a secondary combustion chamber for each cylinder The main space is limited in part by the associated piston and communicates with the adjoining space via a torch nozzle sets 'inlet and outlet valves' for the main combustion chamber, a metallic conduit in communication with the exhaust valve assembly, an auxiliary inlet for the adjoining room with another metallic line, and a device for igniting the combustible one Mixture in the adjoining room, with at least some of the metallic lines in a heat exchange ratio stands with each other, so that combustible mixture in the auxiliary inlet pipe through the exhaust gases in the outlet pipe is heated.

Preferably at least a portion is the auxiliary inlet conduit assembled with the outlet pipe. The condensation of fuel in the auxiliary intake pipe is therefore reduced to a minimum and thereby the Incineration improved. Preferably a main

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inlet conduit is provided which is connected to the inlet valve assembly communicates and is thermally insulated from the outlet line as well as from the auxiliary inlet line. Therefore, the lean mixture is not exposed to the heat of the exhaust gases, so that it is kept in a cool state in order to prevent the filling efficiency from being lowered by thermal expansion.

An embodiment of an internal combustion engine according to the invention is described in more detail below, for example in connection with the accompanying drawing FIG. ¹ , which shows a view of the internal combustion engine in section.

In the accompanying drawing, the internal combustion engine is denoted generally by 1, which has a piston 2 which forms a wall of a main combustion chamber 4. The main chamber 4 is supplied with a lean fuel-air mixture through a main inlet duct 3, which supply (3Ui ^-1 Ch a conventional inlet valve (not shown) is regulated Tin serves to ignite a rich mixture which is fed to the adjoining chamber 7. This rich mixture is fed in via a duct 8 via an inlet valve 17 from an auxiliary carburetor 10. A double carburetor supplies a lean mixture to a separate inlet duct 3.

The inlet duct 8 for the rich mixture is arranged in such a way that it is in a heat exchange relationship with the exhaust gas duct 12, 13, so that heat is transferred from the exhaust gases to the supplied rich mixture for the adjoining space 7. However, the line 3 for the lean mixture is separated from the lines 8 and 13, so that

no heating of the lean mixture takes place. The heat exchange between lines 8 and 13 is achieved by assembling the lines.

An exhaust valve 11 is through a rocker arm IG actuated by a camshaft 15 from which the auxiliary inlet valve 17 is also actuated.

The main inlet valve (not shown) is also operated from the camshaft 15 by conventional means.

In operation, the lean combustible mixture is fed into the main combustion chamber 4 through a separate inlet duct 3 from a carburetor 9 with an air cleaner 14 sucked in. Fat, combustible mixture is fed into the adjoining room from the carburetor 10, which is also where the air cleaner is located 14 is attached, through the inlet channel 8 and .jüber the auxiliary inlet valve 17 sucked. After During combustion, the gases pass over in the main combustion chamber 4 the valve 11 and get into the outlet channel 1% 13, wherein the heat of the exhaust gases is used to a Condensing the rich mixture flowing through the auxiliary intake port 8 occurs to prevent.

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Claims (3)

139/68 23U1066 Patent claims: ll./ four-stroke piston internal combustion engine with spark ignition, characterized by a main combustion chamber (4) and a secondary combustion chamber (7) for the or each cylinder, wherein the main combustion chamber is limited in part by the associated piston (2) and with the Adjacent room (7) communicates via a torch nozzle (5), an inlet valve and an outlet valve (11) for the main space (4), a metallic line (12, 13) which is in connection with the outlet valve (11) stands, an auxiliary inlet (8, 17) for the adjoining room (7) in the form of a further metallic line (8), and a device (6) for igniting the combustible mixture in the adjoining room (7), at least some of which the metallic lines (8, 13) in a heat exchange ratio stands with each other, so that the combustible mixture in the auxiliary inlet line (8) through the exhaust gases in the exhaust pipe (12, 13) is heated. 2. Machine according to claim 1, characterized in that at least part of the auxiliary inlet line (8) is assembled with the outlet pipe (12, 13). 3. Machine according to claim 1 or 2, characterized in that 309830 / OUG that a main inlet line (3) is provided which is in communication with the inlet valve and from the outlet line (12, 13) and the auxiliary inlet line (8) is thermally insulated. 309830/0440