Abstract: Disclosed is a method for controlling the spark ignition in an Otto engine, of the type including an ignition voltage-generating ignition system with a spark plug electrode fixedly arranged in the combustion chamber of the engine and with an earth electrode co-operating movably therewith and joined fixedly to the engine piston in question. For the purpose of producing a controlled ignition moment in such engines the ignition moment is controlled so as to occur later and with shorter sparking distance when the engine load increases from light load to whole load. At the same time, the ignition voltage necessary for spark formation is controlled so as to vary within relatively narrow limits over essentially the whole load range.

Abstract: The invention relates to an ignition cassette unit for an ignition system for a multi-cylinder Otto-type four-stroke engine equipped with at least one spark plug per cylinder, the ignition system including for each spark plug an ignition device (61,62) connectible to said spark plug in the engine substantially without cables, the ignition system also incorporating a control unit (8) sending signals in response to the engine operating conditions for triggering sparks at the spark plugs in a predetermined order. In order to ensure, in such ignition sytems, transmission of maximum ignition voltage to the engine spark plugs and enable simple and safe handling of the ignition system during service the the like, the invention is mainly distinguished in that the ignition devices (61,62) to at least two adjacent spark plugs are included in a common, handleable unit, a so-called ignition cassette (70).

Abstract: The invention relates to an ignition system for a multicylinder Otto-type four-stroke engine equipped with at least one spark plug per cylinder, the ignition system including for each spark plug an ignition device (61,62) connectible to said spark plug in the engine substantially without cables, the ignition system also incorporating a control unit (8) sending signals in response to the engine operating conditions for triggering sparks at the spark plugs in a predetermined order. In order to ensure, in such ignition systems, transmission of maximum ignition voltage to the engine spark plugs and enable simple and safe handling of the ignition system during service and the like, the invention is mainly distinguished in that the ignition devices (61,62) to at least two adjacent spark plugs are included in a common, handleable unit, a so-called ignition cassette (70).

Abstract: An arrangement for exhaust gas recirculation in a supercharged internal combustion engine has an intake system and an exhaust system joined to each other via a conduit for recirculating exhaust gases to an intake conduit. This recirculation is controlled by a valve in response to the engine intake pressure, said valve having control means comprising an outer and an inner chamber separated by a movable membrane attached to which is a valve member regulating the flow through the conduit. Said valve member is acted on via the membrane by a spring in the outer chamber, which chamber is connected via a conduit to the intake conduit immediately upstream of the idle position for a throttle valve pivotably mounted in the intake conduit. The inner chamber is connected via a conduit to the intake conduit upstream of the connection of the conduit from the outer chamber but downstream of a compressor of the intake system.

Abstract: A method of avoiding abnormal combustion, so-called knocking, in an internal combustion engine, where a parameter representative of the combustion conditions in the engine is monitored. When abnormal combustion occurs, a signal representing such abnormal combustion is generated and is used to initiate an adjustment of the engine operating conditions by lowering the engine induction pressure so as to reestablish normal combustion. There is also provided an arrangement for avoiding abnormal combustion.

Abstract: A spark ignited Otto cycle type engine have a fixed compression ratio which is supplied with a mixture of air and fuel having an octane number lower than that which would normally be appropriate for the compression ratio. The engine operates in a range below a predetermined high load without spontaneous combustion of the fuel-air mixture but will be susceptible to spontaneous combustion when operated above the predetermined high load. The engine includes means for controlling combustion of the fuel-air mixture when operating above the predetermined high load in a manner to decrease the efficiency of the engine and to prevent spontaneous combustion which would otherwise occur.

Abstract: Arrangement with a combustion engine having a fuel dosing carburetor, a throttle and a compressor situated in the engine inlet system. The carburetor is positioned upstream of the compressor and the throttle is positioned downstream of the compressor.