2.3 Racks

A rack can be considered as a gear with an infinite radius. It is used to transform rotary motion into translational motion and vice versa. The toothed gear that meshes with the rack is called a pinion.

Unlike the spur gears, the most important mechanical value for the racks is the maximum stress that can be applied on a single tooth. This is due to the fact that, on this particular transmission element, no torque is applied.

The maximum stress values reported in the tables of the datasheet are the results of laboratory tests in which the force applied to the tooth of the rack increases until the tooth breaks. The maximum stress values reported in the datasheet show the maximum stress that can be applied when a single tooth is meshed.

increase in the number of meshed teeth will not linearly increase the maximum applicable stress because only one tooth will ever work in optimal conditions.