Modernization of the fuel supply system in the internal combustion engine by electronic control of the ring valve

The research was carried out in order to develop a method for skipping fuel supplies (turning off individual piston strokes) at low frequencies of crankshaft rotations and at partial engine operating modes with direct-acting fuel supply systems to increase fuel efficiency. The developed method is easily implement using a ring-type discharge valve with electronic control. A valve made in the form of a split elastic ring and installed in a high-pressure line above the plunger pair controls the fuel supply. An electromagnet, located in the cavity of the annular valve, controls the valve, using an electronic regulator, acting at the right moment according to the signals coming from the sensors of the engine crankshaft speed, the volume of incoming air and the position of the piston. The proposed direct-acting fuel supply system with an electronically controlled ring valve reliably ensures the speed and load characteristics of the engine by affecting the number of cyclic feeds. With a decrease in the load and speed of the engine crankshaft, the number of cyclic fuel supplies decreases due to a decrease in signals sent to the electromagnet winding and, as a result, the valve does not attract the fuel and misses the fuel supply. Reducing the unevenness of the fuel supply by the dynamic component that occurs when the supply is switch off is ensured by reducing the inertia of the regulator due to the electronic control of the ring valve. The developed mathematical model of a direct-acting fuel supply system with an annular discharge valve allows us to reveal the relationship of fuel supply parameters with the design dimensions of the split ring. Such direct-acting fuel supply system with an electronically controlled discharge valve allows, due to the skipping of working strokes in low-load and idle modes, redistributing the provided amount of fuel to the working cylinders, significantly reducing fuel consumption

Improving the operational efficiency of tractors by ensuring their ability to perform work

Development of agriculture in conditions of market relations is accompanied by aggravation of the problem of efficiency of use of technics. In this connection, the task of scientists is to increase the actual volume of work performed by tractor units, reducing the cost per unit of production. The high cost of tractors, the lack of personnel, the reduction of technical equipment of farms and the increase in the volume of products produced in the agro-industrial complex, natural and climatic conditions impose special requirements on technical service to maintain tractors in working conditions. The working state of tractors is the state at which values of parameters, which characterize ability to execute the given functions, correspond to normative-reference and design documents. During the operation of tractors in agriculture under the influence of various factors, wear of their parts and knots. The indicator determining the value of wear is the residual resource of aggregates and knots of technics. In the article the questions of influence of residual resources of basic aggregates and systems of tractor on frequency of failures of various groups of complexity are considered. Experimental research on determination of dependencies of residual resources of tractor units and frequency of failures of different groups of complexity, on the basis of which the rules of replacement of the unit whose resource are exhausted, is carried out, i.e. is replaced with a full of the resource (new) or on the aggregate after overhaul

Research of dynamics of turning of machine-tractor aggregate with tractor on wheeled-crawler mover

In the article theoretical preconditions of a description of dynamics of manoeuvrability of machine-tractor, aggregates with a wheeled-tracked mover are considered. For a machine-tractor aggregate with half-tracked progress theoretical formulas of determination of an actual turning radius, the moment of resistance of turn and torque for rotation are obtained. The theoretical preconditions are confirmed by experimental research of the manoeuvrability of the machine-tractor aggregate with the tractor on a halftracked progress, made as the experimental sample. The dependences of the turn coefficient and the resistance coefficient of the turn are obtained, and the correlation coefficients and their significance have confirmed the existence of a stable connection between the changing parameter and the response function. Proceeding from theoretical and experimental research, it is possible to draw a conclusion that the manoeuvrability of the tractor with a wheeled-crawler mover does not concede to the tractor in the basic execution