be described hereinafter in great detail the input shaft 37 is disposed along the axial center of the casing 23 with its outer end projected out of the casing 23 and it is rotatably journaled in a plurality of radial bearings 41 also the input shaft 37 is fixed at its projecting outer end with a driving pulley 43 secured thereto by a key 45 so that it may be constantly driven during operation it will be readily seen that the driving pulley 43 is driven by the motor 11 through the belt or belts 13 when the multiple disk clutch assembly 1 is mounted in the mechanical press 3 as shown in fig1 the casing 23 includes also an output shaft 47 which is disposed in coaxial relation with the input shaft 37 along the axial center of the casing 23 and with its outer end projected out of the casing 23 the output shaft 47 is formed at its inner end with a large diameter portion 49 which is provided with a plurality of splines 51 a plurality of axial holes 53 and a single larger axial hole 55 the splines 51 are axially formed like teeth of a spur gear around the outside of the large diameter portion 49 of the output shaft 47 and the axial holes 53 are axially formed through the large.