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In the design of gearboxes and transfer boxes of heavy-duty vehicle`s transmissions, sliding bearings are often used as supports for gear wheels. Analysis of the results of statistical processing of gearbox parts failures and transfer boxes of wheeled tractors with a pulling force of 30 kN indicates the need to improve the reliability of the sliding bearings of the gear wheels. Such plain bearings ensure free rotation of the gear wheels in case of the torque transmission absence, and when locked by a clutch, the radial load of the gear wheel is sensed, while operating in the slipping rolling mode. Such units are poorly understood and in the technical literature sources there are no recommendations for their engineering, which often leads to errors when selecting operation gaps and press fitted in gear wheels. The manufacturers of the transmissions assemblies replaced the plain bearings, which in this case are made of metal-ceramic bushes, for roller bearings.

In connection with the tightening of environmental standards, the leading manufacturers of marine low-speed engines are carrying out intensive work on their conversion to gas fuels. Due to the design features in this class of engines, only internal mixture formation is possible. For the organization of which two different approaches are possible. To date, only two are currently implemented. MAN started production of engines with gas fuel supply to the working cylinder under high pressure at the end of the compression stroke, and WinGD under low pressure at the beginning of the compression stroke. The analysis, performed by the authors, showed, that increasing the pressure before the gas supplying mechanisms to 3.5...6.0 MPa can reduce the residence time of the gas-air mixture in the working cylinder and reduce the likelihood of detonation combustion.

This article deals with the features of the thermal preparation system application on automobile engine, the heating of which to operating temperatures is carried out on petrol, and subsequent operation on liquefied petroleum gas. The main element of the heat treatment system is a phase-transfer heat accumulator, the task of which is to minimize the engine warm-up time and, therefore, reduce petrol consumption on warm-up modes. An information system has been developed (is being used) for remote monitoring and control of the thermal preparation processes of an engine with a thermal accumulator. The results of experimental studies on a passenger vehicle engine under various operating conditions have confirmed the effectiveness of using a phase-transfer heat accumulator to reduce the heating time of the coolant and reduce the consumption of petrol to warm up the engine.

The bulk of automobiles are equipped with ABS currently. Having of automatic devices that prevent vehicle wheels from locking and skidding does not require consideration of the normal reactions on the front and rear vehicle axles wheels’ changes dynamics. However, ABS malfunction is possible for various reasons, and in this case the braking system must provide the safety vehicle braking. To provide this, it is necessary to return to the problem of choosing the rational braking forces distribution between the wheels of the front and rear axles.

New solutions for actual problems of determination the efficient distribution of braking forces between the axles of the vehicle, and the stability and drivability of two-axles vehicles at service braking are received in the thesis. It permitted for the first time to determine the Law of distribution of the braking forces between the axles, that ensuring straight-running stability of two-axle vehicle at service braking, to obtain the ideal characteristics for the braking system of two-axle vehicle at service braking and to determine possible values for the distribution of braking force on the front axle. The drivability criterion at service braking obtained further development; it is offered to use boundary at gripping front or rear wheels angular vehicle acceleration on the road.

The article deals with experimental and theoretical researches of hydraulic processes in a system of accumulator fuel supplying (Common Rail) during the diagnosing while the vehicle idling and during the acceleration. The aim of the work is to assess the efficiency of the offered diagnosing technique as the point of view of cutting-down time for troubleshooting and as the point of view of increasing reliability of failure localization. Feature of the presented approach is that it uses the analysis of fuel pressure fluctuations in the high pressure hydroaccumulator, synchronously with the analysis of rotary speed of an engine crankshaft and the steering signals on electromagnetic magnets (or piezoelements) of injectors. The technique uniting preliminary diagnosing of Electronic Engine Control (EEC) and components of the vehicle fuel units during the constant remote monitoring process, and deep, detailed diagnosing at a service station is described.

The results of this work is allowed to identify a number of cybersecurity threats of the automated security-critical automotive systems, which reduces the efficiency of operation, road safety and system safety. Wired or wireless access of the information networks of the modern vehicles allows to gain control over power unit, chassis, security system components and comfort systems. According to the evaluating criterion of board electronics, the presence of poorly-protected communication channels, the 75% of the researched modern vehicles do not meet the minimum requirements of cybersecurity due to the danger of external blocking of vital systems. The revealed vulnerabilities of the security-critical automotive systems lead to the necessity of developing methods for mechanical and electronic protection of the modern vehicle. The law of normal distribution of the mid-points of the expert evaluation of the cyber-security of a modern vehicle has been determined.

Plane bearings are used as rotating bearings for gear wheels of vehicles transmissions. The design of these units provides for the operation of bearings in two main loading modes: sliding mode (without load transfer) and rolling mode with slipping motion (with load transfer). The mode of sliding bearings operation in the rolling and slipping mode is not sufficiently studied, which makes it impossible to quantify at the design stage the influence of the operating conditions of the vehicle on wear processes, and, therefore, on their reliability. It is necessary to take into account the fact that the condition of the bearing coupling affects the conditions of the gearing. The results of statistical studies of wear and accelerated wearing tests of sliding bearings of gears of a wheeled tractor show the low reliability values of both gear wheels and sliding bearings.