DEM0022297MA - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

Registration date: March 11, 1954. Advertised June 21, 1956

GERMAN PATENT OFFICE

The invention relates to a two-stroke internal combustion engine with a crankcase pump, the inlet of which for the fuel gas into the crankcase controlled by a rotary valve driven by the crankshaft and in its effective cross-section is regulated as a function of the engine speed.

In a known machine of this type, the rotary valve consists of two circular segment discs, the radial edges of which form the slide opening which is variable in cross section. The segment discs are rotatable against each other depending on the speed by a centrifugal pendulum, so that the slide opening becomes smaller with increasing speed. This version has the disadvantage that it is too expensive and prone to failure and a tight seal of the fuel supply line without additional Cannot reach the means. It also significantly interferes with the balancing of the crankshaft and their control function can easily be carried out by unauthorized persons by replacing the centrifugal pendulum spring to be changed.

In another known machine of this type, in which the fuel gas through a hollow Bearing journal of the crankshaft is supplied and the radially pierced journal wall itself as a rotary valve is used, the regulation of the effective flow area for the fuel gas

609 546/211

M 22297 Ia / 46a ⁹

caused by a cylindrical grommet which is inserted into the hollow shaft inside the crankcase and whose outlet openings are more or less covered by a cuff, which is adjusted against the action of a spring by centrifugal force. This machine avoids although some of the disadvantages of the former machine; but the disadvantage remains that the control function of the cuff can easily be changed, which is of particular importance is when maximum speeds are stipulated which must not be exceeded. It is coming in this machine but the disadvantage that the adjustment forces of the cuff because of their a short distance from the crankshaft axis are relatively small. That is even more true of the also proposed further embodiment of this machine, in which the axial Bore of the shaft journal passed through the adjoining crank web and the opening can be regulated by a flat slide depending on the speed. In addition, is between The space for movement of the crank and the crank web only has a very narrow space, so that a reliable execution of this slide can hardly be attached at this point.

There is also a two-stroke internal combustion engine with flat rotary valve known in which the Fuel gas behind the rotary valve through an opening in the crank web outside the shaft axis passes through. However, this machine does not have a gate valve that controls the fuel gas supply when a maximum speed is reached.

The invention is based on the object of the known two-stroke internal combustion engines avoid existing disadvantages with rotary valve control. The invention consists in that the fuel gas supply through the crank web in a known manner at the greatest possible distance Relocated from the axis of rotation of the crankshaft and the governor in the form of a radial linearly guided centrifugal slide is housed in a slot in the crank web. Through this a speed limiter protected against external interference is created with relative large adjustment forces and is therefore very reliable. It does not claim any additional Space and does not change the balance of the crankshaft to any noticeable extent.

The drawing shows an embodiment of the invention, namely in

Fig. Ι ■ a vertical section through the crankcase and in

Fig. 2 a section perpendicular to the crankshaft through the crank web and the slot with the centrifugal slide.

In the crankcase α , the crankshaft b is mounted in the usual way. The gas mixture is fed through a channel c and controlled by the flat rotary valve d , which seals with a collar e against the crank arm f , which is circular at this point, in order to prevent fuel gas from escaping through the gap g between the flat rotary valve and the crank arm. The fuel gas can therefore only flow through the opening h of the crank web in order to get into the interior of the crankcase. The piston and piston rod are omitted from the drawing for the sake of clarity. The crank web / is provided with a slot i in which the centrifugal slide / is guided in a radially straight line (Fig. 2). At rest and at low speed, the centrifugal slide / is held in the inner position by means of helical springs m. When a certain speed is exceeded, the centrifugal force acting on the slide predominates, so that the slide slides outwards and closes the opening in the crank arm.

Claims (3)

Patent claims: 1. Two-stroke internal combustion engine with a crankcase pump, the inlet of which is controlled by a rotary valve driven by the crankshaft and in which the incoming mixture is regulated by a gate valve after flowing through the control element, which is guided radially in a straight line to the axis of rotation of the crankshaft and is under spring tension in such a way that when it is reached a certain speed the spring tension is overcome as a result of the centrifugal force of the gate valve and an opening in the crank web is closed by the gate valve, characterized in that in a known manner the control opening (d) of a flat rotary valve and the opening (h) in the crank web parallel to The crankshaft axis of rotation are arranged outside the axis of rotation and coaxially to one another and that a flat gate valve (/) is provided for the opening in a slot (1) of this crank web. 2. Two-stroke internal combustion engine according to claim i, characterized in that a 105th regulator spring (in) is arranged on each side of the centrifugal slide (J) . 3. Two-stroke internal combustion engine according to claim ι und.2, characterized in that the flat rotary valve used for inlet control is provided with a collar (V), ·. the against the edge of the. circular at this point trained crank web seals. Referred publications:
German Patent No. 804,978;
French patent specification No. 586 304,
310. ■: 1 sheet of drawings 1 609 546/211 6.56