Method For Limiting Torque Transmitted by Elongate Driving and Driven Members

Abstract

An apparatus and method for limiting torque transferred from an engine or motor to a drive shaft or other components. In some embodiments, the torque-limiting device has a spindle disposed within both coupling flanges to increase the resistance to radial forces and to maintain coaxial alignment of the flanges and attached drive shafts. In some embodiments, the axial spacing of bearings that enable rotation of the coupling flanges is based upon the diameter of the spindle. In another embodiment, torque-limiting devices that maintain coaxial alignment may be used to modify vehicle drive shafts to enable long distance towing for long durations at high speeds.

What is claimed is: 
     
         1 . A method of towing a vehicle having a drive shaft with a torque limiting device to facilitate towing, the torque limiting device having a first coupling flange and a second coupling flange that rotate relative to one another, further wherein said first coupling flange has a first longitudinal axis and said second coupling flange has a second longitudinal axis, wherein said first coupling flange is connected to a first section of a drive shaft and said second coupling flange is connected to a second section of the drive shaft adjacent said first section, the method comprising:
 rotating the first section of the drive shaft relative to the second section of the drive shaft so that said first longitudinal axis remains substantially coaxial with respect to said second longitudinal axis for more than one minute.   
     
     
         2 . A method according to  claim 1 , wherein the vehicle includes wheels indirectly connected to the second section of the drive shaft so that when the wheels are caused to rotate by towing the vehicle the second section of the drive shaft and second coupling flange are caused to rotate, wherein the rotating step includes towing the vehicle so as to cause the second section of the drive shaft and second coupling flange to rotate relative to the first section of the drive shaft and first coupling flange. 
     
     
         3 . A method according to  claim 1 , wherein the rotating step is performed so that the first section of the drive shaft rotates relative to the second section of the drive shaft at speeds in excess of 2500 RPMs. 
     
     
         4 . A method according to  claim 2 , wherein the rotating step includes towing the vehicle for more than one hour. 
     
     
         5 . A method according to  claim 1 , wherein the first coupling flange is securable to the second coupling flange by at least one mechanical fuse, further wherein the rotating step includes removing any mechanical fuses coupling the first coupling flange with the second coupling flange before rotating the first section of the drive shaft relative to the second section of the drive shaft.