Lozica Ivanović

Modeling of the Meshing of Trochoidal Profiles With Clearances

This paper explains development of the general mathematical model of trochoidal gearing that can be applied for gerotor pumps and cyclo reducers. The model analyzes geometry and physics of the gearing pair in trochoidal pump where the outer gear has one tooth more than the inner gear. The inner gear profile is described by peritrochoid equidistance and the outer gear profile by circular arc. Mathematical model of gearing with clearances is based on the principle of an ideal profile development. Minimum clearance height between teeth profiles in relation to instantaneous gear ratio is determined. The influence of gear profile geometrical parameters on gearing process, clearance height change, and pulsation of drive moment is analyzed and presented in numerical examples. Obtained results can be used for the design of the trochoidal gearing where accurate and silent operation is required. [DOI: 10.1115/1.4005621]

Modelling of Trochoidal Gearing at the Gerotor Pump

In this paper, generating and analyzing of meshing of the gear pair profiles with internal trochoidal gearing is considered. Firstly, parameter and vector equations of the conjugated tooth profiles are defined. The forces and torques which are acting on the gear pair of the gerotor pump are also considered in this paper. The problem of the contact forces determination is complex because the pumps with trochoidal gearing loading are transmitting simultaneous at the more contact points. The fluid pressure forces which are acting on the tooth gear flanks, and which are depended of the numerous influential parameters are also given. From this reason, one simply physical model and corresponding analytical method are applied. The aim of this analysis is to determine the load distribution at the trochoidal pumps with fixed axes of shafts. The calculation of the contact stresses and the choice of construction solution with the minimum contact tooth loading can be done on the basis of the obtained results.

Analysis of the flow rate and the volumetric efficiency of the trochoidal pump by application of Taguchi method

Original scientific paper Taguchi method has been used to analyse the influence of the coefficient of the trochoid radius, the number of revolutions and the working pressure on the change in the flow rate and the volumetric efficiency of the trochoidal rotary pump with internal gearing. The coefficient of the trochoid radius, as a geometrical parameter and the number of revolutions and the pressure, as working parameters are considered influential factors in this paper. Taguchi robust design and orthogonal matrices have been applied to design the experiment and to determine the degree of the factors influence, as well as their optimum values. The highest values both for the flow rate and the volumetric efficiency have been obtained for the coefficient of the trochoid radius of 1.375, the number of revolutions of 2000 min and for the working pressure of 1 bar. The conformation of the experiment shows that Taguchi method can be successfully used for selection of the optimal combination of parameters so that the maximum volumetric efficiency of the trochoid pump can be achieved.

Testing of the Electromotor Power Transmitter Properties

The requirements set, which modern gear power transmitter have to fulfill, are quite complex. The modern gear power transmitters are working on higher and very fluctuating load level, while need to be even more smaller, efficient, quieter, easier to produce and finally they have to cost less. Although the latest development made in the analysis and simulation of power transmitter, experimental testing is still essential. This paper presents the experimental method of measurement and assessment of working properties of electromotor power transmitter. The testing method presented in this paper is specific application-oriented full-scale testing with simulation of working conditions. Testing of the characteristic properties values was conducted on a three stage electromotor power transmitter and on the production series of five pieces. The paper presents two kinds of examination, the method of serial examination and the method of occasional (reduced—standard) testing. Experimentally determined characteristics and performances of power transmitters in working conditions represented real result of its design and used manufacturing processes. The obtained results are used as essential data for design modifications and its proper qualification, so as developing completely new designs. Also, results obtained by the same methodology represented the current technical condition of the examined power transmitter and could be used as condition diagnosis of the power transmitter elements without the need of their disassembly. The needs for standardizing of the testing methods are pointed out.