Browse Publications Technical Papers 2009-01-1255

Technology for Prediction of Torque Capacity during Operation of AT with Focus on Friction Properties of Facing Materials in Multiple Plate Clutches 2009-01-1255

The project discussed in this paper focused on the torque transmission characteristics of facing materials in order to enable desktop prediction of the torque capacity of the multiple plate clutches used in automatic transmissions (AT). The amount of torque transmitted by the facing materials themselves is affected by the temperature, contact pressure and sliding velocity of the friction surfaces. An analytic model of a test apparatus was therefore constructed, and the friction properties of the facing material were identified from the amount of torque transmitted. Next, a torque capacity prediction model, able to simulate the flow of torque transmission in the transmission, was constructed. This enabled torque capacity in an operating AT to be predicted for the first time with an accuracy to within ±5% of measured values. In addition, an examination of the friction force vectors of the clutch disks showed that torque capacity is affected not only by friction force components acting in the direction of rotation, but also by simultaneously produced friction force components acting in a radial direction. The project also showed that the developed method of predicting torque capacity is effective for ATs with differing clutch layouts.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 17% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:

Power-By-Wire Piezoelectric-Hydraulic Pump Actuator for Automotive Transmission Shift Control


View Details


Study on a New Type Clutch Auto-operating System for Heavy-duty Commercial Vehicle


View Details


Development of All New 7-speed Automatic Transmission for RWD Vehicles


View Details