Abstract: Diesel fuel preheaters with a heat exchanger and electric heating serve, for example, at low temperatures to maintain the flowability of diesel fuel and furthermore to quickly heat diesel fuel to achieve defined conditions for a fuel conserving and emission reduced combustion of the fuel and a better engine performance. The diesel fuel preheaters are provided with an integrated control unit and are adaptable to various engines and operational conditions. A special electric heating element in cooperation with the integrated control unit and the heat exchanger provide a fast and economic preheating of the diesel fuel. Furthermore, various advantageous couplings and mechanisms for the regulation of the heat transfer from the heat-delivering medium such as cooling water to the diesel fuel at the heat exchanger are shown and described.

Abstract: An electrmagnetic intermittent injection valve for supplying fuel to an intake duct of an internal combustion engine comprising a hollow body having a fuel inlet for admission of fuel from a fuel supply, a fuel outlet for supply of fuel to an intake duct of an internal combustion engine, and a fuel return for returning fuel back to the fuel supply. A ball valve is movable in the body between a first position in which the fuel outlet is closed and a second position in which the fuel outlet is open. A spring acts on the ball to urge the ball to the first position. A soft iron core is disposed in the body in facing relation with the ball, the body including a housing end portion of soft iron facing the ball valve. A coil in the body serves for energizing the core and the housing end portion for producing a magnetic field having lines of flux acting on the ball valve to urge the ball valve to the second position against the resilient opposition of the spring.

Abstract: A device for the speed-dependent closing limitation of a selectively adjustable carburettor main throttle, which is prestressed in the closing direction, includes a variably positionable throttle stop for effecting a substantially complete closure of the main throttle above a rotational speed switching threshold higher than the idling speed. Such a closure interrupts the supply of fuel and air. The throttle stop causes an idling minimum opening position of the main throttle below the switching threshold. The device includes an electromagnetic valve which operates when the speed drops below the switching threshold. The electromagnetic valve has a valve outlet and a pair of valve inlets. A diaphragm box divided into separate chambers is mechanically connected with the throttle stop and one chamber is continuously vented. When the speed is above the switching threshold and also when the ignition is turned off the valve outlet is in flow communication with one of the valve inlets.