A variable ratio spring return for a bass drum pedal includes a bass drum
pedal of the type having a driveshaft mounted on a frame for rotation in
a positive direction from a rest position to an impact position on a
longitudinal axis of the driveshaft. A spring return assembly connected
between the frame and the driveshaft biases the driveshaft in a negative
direction from the impact position towards the rest position. The spring
return assembly includes a spring with ears at opposing ends, one ear
connected to the frame and the other ear connected to a cam-shaped hub
mounted on the driveshaft. The hub has a peripheral edge that varies in
radius from a small radius at an upper end to a large radius at a lower
end. A belt has a first end connected to the upper end of the hub and
extends downwardly around a forward peripheral edge of the hub to a clip
that receives the upper ear of the spring. A second end of the belt is
connected to the upper end of the hub and has a second run extending
downwardly therefrom along the rearward peripheral edge of the hub to the
clip. A pivot arm is connected to the hub and has an outer peripheral
edge that forms the lower portion of the hub forward peripheral edge.
Pivoting the arm outwardly from the hub changes the radius of curvature
of the lower forward peripheral edge of the hub.