Analysis of the effectiveness and the possibility of creating an auxiliary braking system for an electronically controlled vehicle of the utility patent No. 153 247

The paper notes that electronic control of work processes in vehicle units and systems is one of the most effective and modern ways to improve their operational parameters. The means of electronics make it possible to increase the average speed of vehicles, reduce fuel consumption, improve controllability, stability, passability and smooth driving, improve braking performance and safety, and facilitate driving. All modern vehicle electronic systems are digital, data transfer rate is up to 1 megabit per second. This allows each sensor to be used for several systems. Dimensions of sensors are gradually decreasing, their speed, reliability, and accuracy are increasing. One perspective way to improve vehicles is the use of an internal combustion engine with electronic control of its braking torque as an auxiliary braking system. The analysis of the patent № 153 247 for useful model "Auxiliary braking system of vehicle with electronic control" is considered and its analysis using the valve timing diagrams. The errors made in the description of the patent were revealed. The description of the intake and exhaust strokes does not take into account the increase in the cylinder volume by the manifold volume due to the opening of the respective valves and the fact that the pressure in the exhaust tract is limited by the preloading force of the engine exhaust brake springs. The electromagnetic valve must have speed by an order of magnitude greater than the regular valves and the same capacity, its springs must have a large pre-pressure so that it does not open under the pressure in the receiver of the regular brake system. For fast pressure release, the electromagnetic valve must open a large flow cross-section as quickly as possible, overcoming the force of the high pressure acting on its disc in the cylinder (7.5 MPa) plus the force of pre-pressure of the valve springs. The formulas for determination of the valve throughput capacity of the valve, analysis of which showed that to ensure a given capacity of the valve by reducing its opening time it is necessary to proportionally increase the height of the rise of electro-magnetic valve or the average diameter that is not always possible. The analysis carried out in the article showed that the efficiency of the proposed system is lower than the declared one, and its creation is impossible because there is no electromagnetic air valve satisfying the requirements for it in this design.

automobile, internal combustion engine, braking torque, electronic control system