conditioning compressor all not illustrated the internal combustion engine 10 also includes a supercharger assembly 20 which is driven by the belt 16 and increases the air pressure within the intake manifold of the internal combustion engine 10 in accordance with conventional practice the supercharger assembly 20 includes a housing 22 which receives supports and protects various components of the assembly 20 the drive belt 16 is received upon a pulley 24 secured to an input shaft 26 which provides rotary energy to the supercharger assembly 20 a first gear train 30 includes a pinion gear 32 which is secured to the input shaft 26 rotates therewith and engages a larger diameter spur input gear 34 the spur gear 34 drives a continuously variable hydrostatic transmission assembly 40 specifically the spur gear 34 is secured to and drives an input shaft 42 of the continuously variable hydrostatic transmission assembly 40 the hydrostatic transmission assembly 40 also includes an output shaft 44 which is coupled to and drives a spur output gear 46 the input shaft 26 also drives a second gear train assembly 50 specifically the input shaft 26 is directly coupled to and drives a carrier 52 which freely rotatably supports a plurality of planet gears 54 on associated stub shafts 56 the planet gears 54 engage a circular ring gear 58 having both internal or female gear teeth.