A New Pump for CVT Applications

2003-01-3207

10/27/2003

Event
SAE Powertrain & Fluid Systems Conference & Exhibition
Authors Abstract
Content
For years, gear and gerotor type pumps have been common in Continuously Variable Transmissions (CVT). In their efforts to improve power density and efficiency of the CVT, engineers are showing interest in other pump types that can better cope with the increasing demands. The raising of CVT pressure levels, to enable higher torque and increased variator efficiency, makes that issues like the hydraulic system effectiveness and efficiency have become increasingly important.
Dual stroke vane pumps provide an answer. They basically form two independent, not necessarily identical, pumps that can work at different pressure levels. They enable the design of cost-effective solutions like switch-able or separated high/low pressure circuits within a single pump unit. This offers a better answer to the hydraulic power requirements of the CVT. Furthermore, the vane design is compact and provides high volumetric efficiency at low speeds even without measures like axial pressure compensation.
Understanding CVT requirements, Van Doorne's Transmissie has focussed on the development of the roller vane (RV) pump to avoid the unfavorable start-up performance, the typical wear behavior and the relatively high production cost accompanying traditional vane pump designs. This has led to several built designs for prototype CVT transmissions showing that the RV pump is ready for the market.
Meta TagsDetails
DOI
https://doi.org/10.4271/2003-01-3207
Pages
15
Citation
van der Sluis, F., "A New Pump for CVT Applications," SAE Technical Paper 2003-01-3207, 2003, https://doi.org/10.4271/2003-01-3207.
Additional Details
Publisher
Published
Oct 27, 2003
Product Code
2003-01-3207
Content Type
Technical Paper
Language
English