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Engineer Alexey Vul from Donetsk assembled an unusual diesel engine: it was arranged according to the Balandin scheme - a crank-slide mechanism was used.
Alexander BUDKIN. Author photo
The idea of such an engine has been known since the last century. Designer of aircraft engines S. Balandin undertook to embody it during the Second World War. However, the fate of this invention was difficult. The fight against the shortcomings of future aircraft engines was too protracted - the war was over, and there the jet engines arrived in time. Competing with them in specific power - this parameter was then highlighted - Balandin's engines could not do. The prototypes turned out to be so imperfect that the unusual motors were essentially oblivious, although they had advantages, which will be discussed below.
What is the mysterious principle of operation of this engine, for the sake of which, as they say, the city garden? Let us digress from history and turn to technology (see. Fig.). Instead of a connecting rod, the Balandin engine uses a rod rigidly connected to the piston. This pair only performs a reciprocating movement (up and down) - no rocking of the connecting rod or “shifting” of the piston. Two rods 2 sitting side by side on the crankshaft 3 are rotated 90 ° with respect to each other. The shaft itself performs a double rotation: around its axis and the axis of the carrier 4. It is precisely this law of motion that allows the power to be transmitted from progressively moving rods to the artfully rotating crankshaft and further to the carrier.
An engine assembled according to such a scheme is much more compact than a traditional one. Lateral forces practically do not act on the piston. And most importantly: in the Balandin scheme, the most vulnerable parts are less loaded. The photo above shows two connecting rods assembled with pistons: to the left of the Balandin engine, to the right of a conventional engine with the same (100 mm) cylinder diameter. In the usual case, the force from the gas pressure is transmitted through a relatively small bearing of the upper head of the connecting rod, then through the bearing of the lower head - it is already larger, but here the loads increase: the inertia forces from rotation are added. There is only one bearing in the Balandin design, and its size is larger than that of the lower head bearing of a conventional connecting rod. We take into account that the inertia forces here are also less, and the lower head of the Balandin's engine is inseparable.
Now about the shortcomings. The main one is the so-called excess kinematic connections. Try to put a rigid rod at the same time on three supports - swinging? The extra support in this example is the excessive connection. To assemble such a mechanism, either high flexibility of the supports or ideal precision in the manufacture of parts is necessary. And since the crankshaft bearings or the shaft itself cannot be made flexible, it remains to rely on the highest manufacturing accuracy or … change the kinematic scheme. On the last path and went engineer Wool. True, while the method of solving the problem is kept secret.
The author’s general approach to the creation of the motor is peculiar. The workflow, as the most difficult part of the work, the follower of Balandin borrowed entirely from the Czech tractor diesel Zetor. I simply rearranged the individual cylinder heads and nozzles from the donor engine, and I precisely copied the combustion chamber and its relative location. Since the piston of the new diesel engine is steel, and therefore hotter, it was nevertheless necessary to introduce changes in the working process: the injection pressure was slightly increased, its duration was reduced, a different injection advance angle was selected.
So from the finished “top” and the original “bottom”, a four-cylinder V-shaped diesel engine with a camber angle of 90 °, and a four-stroke one, was obtained. Stop, sophisticated readers will say, with such a scheme it is impossible to achieve a uniform alternation of flashes: after dividing the duration of a full cycle of 720 ° into four cylinders, we get 180 °. It is true that here the flashes alternate unevenly: 0 °, 90 °, then a pause of 270 ° and again 0 ° and 90 °. I had to use a Stanadyne distribution type fuel pump with counter-moving plungers, designed for an eight-cylinder engine, and send fuel from four “extra” fittings to the drain. A few more units were borrowed from different cars: the Mitsubishi generator, the Daewu starter, liners from KAMAZ, the Garrett turbocharger from Volkswagen will appear in the near future, and the engineer will not recall the radiator taken from whom. Plus a huge amount of DIY parts. And all this, when assembled, works successfully.
Of course, to assemble an unusual engine in garage conditions, especially a diesel engine, is an extremely difficult task, almost unrealistic. So I want to know what is the secret. It turns out that nothing new: patience, work, vast experience in the repair of modern foreign diesel engines and turbochargers for them (!). Once, he independently made even a plunger pair for fuel injection pump - nothing, it worked.
But after all, such operations require a serious machine park? It was also created on its own and also not in one year. It was required to make a test bench with a double-acting load motor - six months of painstaking work and the bench was ready. The “minor” problems that arose during the course of work were helped by the home library. After that, say that the Kulibins have been transferred!
Well, what is not a factory product, except that the collectors give out manual assembly.