Die vorliegende Arbeit leistet einen Beitrag zur Optimierung der Auslegung und des Betriebsverhaltens von hohlradgetriebenen Innenzahnradpumpen. Es werden allgemein gültige Auslegungsregeln für industriell umsetzbare Innenzahnradpumpen entwickelt. Die erarbeiteten Gestaltungskriterien führen vornehmlich zu einer Minderung von Druckpulsationen und Druckwechselkräften. Für die Verifikation der Auslegungsregeln wird der Druckverlauf in der Zahnkammer mit einem im Zahnfuß eingebauten Miniaturdruckaufnehmer gemessen. Durch das Antriebskonzept können bei hohlradgetriebenen Innenzahnradpumpen aufgrund exzentrisch angreifender Kräfte Verkippungen an den Pumpenrädern auftreten. Diese Verkippungen werden unter dynamischen Bedingungen über zwei Wirbelstromsensoren erfasst. Nach den erarbeiteten Regeln ausgelegte hohlradgetriebene Innenzahnradpumpen zeichnen sich bei ähnlichen Herstellungskosten durch niedrigere Schallemissionen als Außenzahnradpumpen aus. Dadurch wird das Potenzial von hohlradgetriebenen Innenzahnradpumpen zur industriellen Anwendung und Umsetzung bewiesen.
Gear pumps are still widely used for the hydraulic power transmission in power transferunits as well as mechanics systems. For the industrial application of the gearpumps, in particular a low noise emission, low manufacturing costs and a high performanceare required. In this respect, comparing the internal gear pumps with externalgear pumps, the former are characterized by lower noise emission, neverthelessdue to higher manufacturing costs are less widespread and investigated.The presented study is concerned with an optimization of the dimensioning and theoperating behavior of the hollow wheel actuated internal gear pumps. The goal is todevelop general rules for dimensioning of industrially applicable gear pumps. Thenew dimensioning criteria lead primarily to a reduction of pressure ripple and forcesarising from pressure variation. By applying the new geometrical method, the geargeometry is dimensioned to avoid the pressure rise in the tooth chamber and consequentlyto reduce the pressure drop in a tooth mesh. A further reduction of pressureovershoots can be accomplished through the adaption of the division bars placed inpump housing with the help of the new calculation method. Determination of thepressure gradient in the pressure rise sequence is realized by applying of an analyticalmethod which permits the calculation of the pressure in the tooth chamber duringthe rotation of the gear. Subsequently, by inserting the grooves in the area of thesickle, it is possible to produce a leakage flow in order to reduce the pressure gradient.For the verification of the dimensioning model, the pressure profile in the toothchamber with the miniature pressure sensor located in the tooth root is measured.For the hollow wheel actuated internal gear pumps due to the acting eccentric forcesa dumping of the pump gears can occur. The occurrence of the dumping under dynamicconditions is monitored utilizing an eddy current sensor. Finally, a characteristicdiagram is developed, which under consideration of the degree of efficiency alreadyin the dimensioning stage enables a reduction of dumping.Based on the arisen results, a Software HGP-SIM for the dimensioning of the hollowwheel actuated internal gear pumps with optimized operating behavior is created.The optimized geometries of the individual pump elements are calculated by enteringthe default data as an input for the sequence of subroutines.The hollow wheel actuated internal gear pumps dimensioned according to the developedrules are characterized by comparable manufacturing costs and lower level ofnoise than the external gear pumps. Thus, the potential of the hollow wheel actuatedinternal gear pumps for industrial implementation and application is proven.