Waddington drive having a cam actuated by an integral flyweight

In a stepless variable stroke drive, the combination of:

• an input shaft journaled for rotation on its axis and being constructed with a radially extending flange;
• a cam having a cylindrical disc mounted with its axis parallel to the axis of said shaft;
• said cam disc having an aperture through which said input shaft projects, said aperture permitting pivotal motion of said cam about said axis of said input shaft;
• a driving connection between said cam and said input shaft, said connection comprising a pivot pin eccentrically fixed in said cam and journaled in said flange, thereby permitting the radial displacement of said disc to positions of varying eccentricity relative to the axis of the shaft;
• means for yieldingly biasing said cam to a given initial eccentricity;
• a relatively massive flyweight integral with said disc and extending radially therefrom for urging said disc toward greater eccentricity with a torque varying as a function of the rotational speed of said input shaft;
• crank means having at one end a follower engagable with said cam for pivoting cyclic movement of said follower, the length of movement of said follower being proportional to the eccentricity of said cam whereby the speed and torque ratios of said drive are varied;
• an output element journaled for rotation;
• means for transmitting the rotational motion of said crank means to said output element;
• a counterweight having a driving connection between said counterweight and said input shaft, said connection permitting the radial displacement of said counterweight from the axis of said input shaft;
• and
• linking means between said cam and said counterweight, said counterweight, said driving connection, and said linking means cooperating to maintain said input shaft in dynamic balance.