Anyone looking for a particularly efficient and economical angular gear is often well advised to go with crown gears. Due to their high efficiency, they are experiencing a comeback today and are increasingly asserting themselves against worm or bevel gears.
Inspired by increasing demand from industry, the design of the gearing parts of the crown gears and their manufacturing technology have been continually improved.
High efficiency with large reduction ratio
In the EtaCrown and EtaCrownPlus crown gears from EBM-Papst, the involute drive pinion is cylindrical. The contact between the pinion and the driven gear is a rolling contact and therefore hardly any friction losses occur. The efficiency is therefore in the range of 90% even at high reductions. This means that almost all of the engine power is available for the drive task. 10% power loss compared to up to 75% for conventional worm wheel designs (depending on the reduction ratio selected) represents enormous savings potential even for small drives. The drive motor can often be made smaller and save installation space and costs.
Optimized gearing technology and improved lubrication
The crown gears in different sizes cover reductions in the single-stage range up to 10:1, two-stage up to 113:1 and three-stage up to 289:1. Together with the Chair of Machine Elements (FZG) at the Technical University of Munich as part of a funding project (Bavarian Research Foundation: AZ-1379-19, clerk: J.-F. Hochrein), ebm-papst has carried out extensive research into gear technology.
In this context, software was developed that can be used for the first time to realistically calculate important parameters for design, such as geometry determinations or tooth contact analyzes under load. The values are validated on powerful test benches and ultimately also serve to optimize production. In order to improve the lubrication of the gears and thereby increase the service life of the gears, a patented separating insert was developed for the housing. This keeps the lubricant where it belongs, namely on the teeth of the gears.
Modular drive system for more flexibility
EtaCrown and EtaCrownPlus are part of the modular drive system from EBM-Papst and can be combined with all DC and EC motors as well as brakes and encoders. Individual complete drive solutions from a single source with coordinated components can be easily put together in the online portal and are ready for dispatch within 48 hours. Typical applications of crown gears can be found in strapping machines as well as in driverless transport and shuttle systems, in gate and barrier drives or in operating tables as a pushing aid.