Friction disc torque limiter

Abstract

A torque limit for interconnecton with a pair of coaxial shafts includes a stack of friction and separator discs alternately splined to drive shaft and to a housing affixed to a driven shaft. In a first embodiment, an annular ring receives a plurality of spring pistons for forcefully engaging the discs with each other. An inner separator disc is secured to an end of the drive shaft and an end plate is fixedly secured to the housing, such plates being in frictional contacting engagement with each other. With the inner disc being affixed to the drive shaft, restricted from both lateral and radial movement with respect thereto, bearing and spline corrosion and wear is minimized such that repair and maintenance costs are significantly reduced. In another embodiment, the discs are interposed between a pair of end plates fixed to an input hub. A bearing is interposed between one such end plate and an end plate of the output hub. The end plate of the output hub is fixedly secured to a stationary end friction plate. A plurality of torque pins interconnect the pair of end plates of the input hub and interconnect separator plates of the disc stack. A plurality of spring cup assemblies within the disc stack define the characteristic break away torque.