International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The result of each measurement consists big or small measurement uncertainty. Many sources of uncertainty, especially in industry measurements, are not well studied and require further researchment. Therefore, it is important to have good knowledge about measurement uncertainty in order to minimize as much as possible.
The results of performed analyse and the study of the opportunities for application of the method of linear regression for determination the calibration curve of the measurement device are presented in this paper. The researchment refers to the assessment of the measurement uncertainty type A and B, as well as the combined and extended uncertainty of the measurement result.
By the fulfillment of the assumption for realization of an engineering experiment, with possession of mathematical, technical and practical experience of the operator and the computer supported analytical process, the calibration curve of the measurement device is determined, as well as the extended uncertainty of the measurement result. In this way, a stable measurement process will be achieved, a consistent measurement result, with an increased level of confidence.

With the analysis and synthesis of the process of crashing, the impact of every factor is estimated in the generation and the development of the accident, and conclusions are drawn regarding the impact of particular elements from the vehicle over the consequences from the accident.

The bumper system is a component of the vehicle intended to reduce the effects of the bumps on the front and the rear of the vehicle, its components and the shell. The cost of the damage and the protection regarding the bumper are the main criteria used to evaluate the efficiency of the impact of the bumper system, especially at low impact velocity.

This paper is representing the results of a deducted analysis and an investigation of the influence of the bumper system alongside its constructive parameters to the extent of the damage in low impact velocity. The investigation is primarily relating to statistical analysis of average damage, overall weighted average damage and variations in the amount of damage.

The diaphragm spring as one of the most important parts of the motor vehicles clutch assembly provides the compressive force on the pressure disk. This force is needed for generating friction between the coupling of the flywheel and the pressure disk and transmitting the torque from the engine to the transmission. Therefore the diaphragm spring is subjected to complex loads. The nominal stress for dimensioning the spring is the tangential stress, which is calculated by the terms of Almen and Laszlo. The aim of this research is analyzing the location of the diaphragm spring supporting points of the clutch assembly and its effect on the caused stresses by using the Finite Element Method.

A friction clutch is mechanical assemblies built between the engine and transmission, that with friction transfers torque from the driving part to the driven (working) part (engine gearbox and other transmission). A diaphragm spring is one of the key component of a clutch assembly. A diaphragm spring is piece to high stress concentration in driving condition, this is often the cause of cracks and crashes spring. The stress of a diaphragm spring is analyzed by finite element method, measurement of stress and performed compare to stress obtained by expressions on Almen-Laszlo.

The automatical variability option of changing the angular velocity is a perspective tendency for coordination of the characteristics of the engine with the working machine. That gives the ability to enhance the productivity of the machine, to simplify their controls and to increase their efficiency factor. All of that led to the creation of many methods and ways of lightly regulation of angular velocity and to a wide variety of constructions and many more. The main disadvantage of the mentioned mechanisms, and other similar mechanisms also, having the continuously variable gear ratio option is that the pump as an element of all of them appears to be only a consumer of power in all duty. The consumed power by the pump turns into heat and heats the oil which makes it necessary for it to be in greater amounts. This lowers the efficiency factor and field of application of mentioned mechanisms and more. For removing this disadvantage a solution is proposed with the realization of a hydromechanical gear with hydrovolume regulating contour.