Perforated sheet material strip - has holes at less than half-inch intervals for wheel spikes

摘要

The continuous strip of sheet material is for use with a machine having spiked wheels feeding it forward. The interval (B) between the holes (4) in rows running along the strip edges is less than a half-inch, the pitch of the spikes being such as to engage in them. It can be a quarter-inch and the spikes can be evenly spaced round the wheel periphery.