z-ent Nowadays the 4-stroke engines produce power only at each second rotation of the camshaft. This increase the size of the engine and mechanical losses. In diesel engine the increasing of the compression relation improves the use but increases also the temperature during the firing time. In this situation the thermical losses increase and the quantity of nitrogen oxides, nox, increases. The side power of the piston is some of the largest source of friction losses and that would be taken away.
Following Z-engine, figures 1-5, base on 2-and 4-stroke working circulation unite and separate compressor part and producing a new mixture to the neighbourhood of the upper part of the cylinderpiston at every circulation of the camshaft at a small angle of the cam, figures 4 and 5. When the changing of the gas is going on according to the mentioned figures 4-5, work is received on the layer of each camshaft. This increases the mechanical efficiency of the engine, at the same time taking of the side power of the piston according to the method illustrated on figures 1-3. On this way the wear of the piston is also reduced essentially. The torque caused of the rotating rods in the piston can be taken of on several ways. According the alternative showed in figure 1 it is realized it is received by means of press bearings placed in the lower end of the rotating rods (needle press bearing). In the 2-stroke engine a part of the flushing air is lost on the outlet side, this can be prevented in the z-engine by means of valve time regulating. Even the"inneS'rotation of the outlet gas is possible (figures 4 and 5).
The outlet valve is open about 180°, typically 60"before the lower dead point-120° after the lower dead point.
The gas changing valve (feeding valve, flushing valve) opening time (time, when largest part of a new mixture is flowing into the cylinder) reaches 20'-30'in the neighbourhood of the upper dead point of the piston, typically 120° after lower dead point-30° before the upper dead point. This short open holding time the piston in the neighbourhood of the upper dead point is enough, because coming gas pressure is fairly high, typical 1-3 bar, when its volume is small and necessary valves are small and light. A low number of revolutions, typical 1000-4000 r/min helps the situation, because from valve engine the inertia powers are proportional to second potency of the rotation speed. Same offered motor cycle engines rotates up to 15000-18000 r/min without problems. When the gas changing valve is closed the piston moves in the direction of the upper dead point (secondary compression) at same time the fuel flushing and fire (firing) and combustion and expansion begin.
The fuel fires or is fired (far example by means of red- hot plug, fuel in flushing, spark or like). A typical work cycle is laid open in figures 1 and 4 and 5. If it is used a separate firing fluid, it can be flushed in the gas changing channel, which is equipped with lamellae in the flow direction. Even all fuel can be flushed in the gas changing channel.
The engine can comprise a heat exchanger in the gas flow between compressor-flushing valve (not shown on the figures). Therefore the temperature of the first compressed gas (typical 3-15 bar) can be controlled (for example from exhaust gases). The production volume of the compressor can be other than the stroke volume of the pistons, therefore the expansion can be made optimal.
For high mechanical advantage the expansion piston and compressor piston are connected to each other, at which the cam machinery get a finely net effect. Even a separate compressor, for example, a screw compressor is possible. In the cam machinery there is two in different directions rotating in cog-wheels synchronized cam shafts. Rotating rods are two, so side power of the piston is eliminated, (even other kind of cam machinery is possible). This cam machinery of new kind makes it at same time possible even first class balance of the mass powers (figures 1-3).
