Speed change and reverser device

A speed changer comprising a rotatable shaft (10) defining a sun axis;

• first and second sun pulleys encircling said shaft;
• the first sun pulley being stationary, and the second sun pulley being rotatable independently of the shaft;
• the first sun pulley comprising a first stationary half section (14), and a second facing half section (16) keyed thereon for axial adjustment;
• the second sun pulley comprising a third half section (46) swivably connected to the second half section, and a facing fourth half section (50) swivably mounted on the shaft;
• the second and third half sections being located between the first and fourth half sections, whereby axial adjustment of the second half section (16) serves to inversely vary the effective diameters of the two sun pulleys;
• a planet pulley carrier (24) affixed to said shaft and extending radially outwardly therefrom;
• third and fourth planet pulleys rotatably arranged on the carrier for orbital movement around the sun axis;
• said third planet pulley being radially aligned with the first sun pulley, and said fourth planet pulley being radially aligned with the second sun pulley;
• said planet pulleys being comprised of a spool (34) and roller (38);
• the spool including two facing end flanges (32) and (40), and the roller being slidably keyed on the spool for axial movement in the space between the end flanges;
• the spacing between the end flanges being greater than the axial dimension of the roller whereby axial adjustment of the roller serves to inversely vary the effective diameters of the two planet pulleys;
• a first V-belt (44) trained around the first sun pulley and third planet pulley, and a second V-belt (51) trained around the second sun pulley and fourth planet pulley.