Rotation Stopper Mk4

grabcad

Although similar to several other of the entries, this incorporates one significant improvement. The use of eccentric cams on the buffers which contact the frame. The holes around the periphery of the bracket are 10mm apart and the cams are offset from the centre by 5mm, meaning that the separation between the two buffers can be infinitely adjustable. The drawings show a restraint bracket on the chainwheel side. This does not attach to the bottom bracket and therefore does not impact the position of the motor assembly. The main brackets are intended to be laser cut and folded from 3mm Stainless Steel (303 or 304 grade). The eccentric cams machined from Aluminium and the buffers cast from Polyurethane or Rubber. Although not as universal as my previous two designs, it would be less expensive to manufacture.