High frequency shifting clutch to reduce the friction losses during the synchronization process

• Applicant: Professor Dr.-Ing. Michael Fister
• Subject Area: Engineering Design, Machine Elements, Product Development ; Mechanics
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 416727006

A shift able friction clutch has the function to engage, disengage, synchronize and allow a time limited speed adaption of rotating shafts. It is used in all areas of the industry. The slipping phase generates high losses based on the principle of the friction clutch. The handling of the friction heat and the attending decrease of friction coefficient are still one of the most important challenges in the field of the clutch development. A new concept ought to shorten the slipping time of the clutch and reduce therefore the friction losses. This research proposal introduces a concept of a so-called mechanical buck converter, which idea is comparable to the power electronic circuit of a buck converter. This novel concept uses favorably analogies between electric and mechanic systems. The synchronous process of the clutch will be more energy efficient. Furthermore, the proposal solves completely the problem of the friction-induced vibration. This way gives a new approach to a classic element of mechanical engineering, the shift able clutch.By the use of detailed multi-body simulation models, the results confirm already the promising potential of the concept. The research application shows the modelling approach and the achieved results. The results motivates to go to the next steps, the transformation to a functional prototype. In the known research areas and in the industry such mechanical step-down converter does not exist in reality.The scope of this research application is to investigate the technical realization of this proposal. A first prototype of the new mechanical step-down converter will be drafted, designed, and manufactured. To check the function, the prototype runs in a real driveline on an existing test bench. Therefore, the control strategy is as well a result of this research work. To show the ability of the concept, the experiment will use known load cycles from typical applications.

• DFG Programme: Research Grants