Plastic Rotary Cutter Rolling Cutting Principle
The rolling cutting principle of plastic rotary cutters is primarily based on replacing sliding friction with rolling friction, combined with blade shape and material characteristics to achieve efficient cutting. The specific principles can be analyzed from the following aspects:
Difference in Friction
Traditional blades (e.g., paper knives) rely on overcoming sliding friction between the material and the blade edge during cutting, requiring greater pressure to penetrate.
Plastic rotary cutters, through their circular blade design, convert sliding friction into rolling friction, significantly reducing frictional resistance (the rolling friction coefficient is approximately 1/10 to 1/30 of sliding friction). As a result, only minimal force is needed to propel the blade forward.
Pressure Concentration Effect
Although the blade of a rotary cutter is made of plastic, its circular edge contacts the material over an extremely small area (theoretically a line). During rolling, the instantaneous pressure is concentrated along the cutting line, causing fibers or molecular structures of flexible materials (e.g., fabric, leather) to undergo "compressive fracture" rather than simple "tearing." This results in a clean, smooth cut.
Blade Shape
Plastic rotary cutter blades typically feature an arc-shaped or thin-edge design. The edges are smooth and possess a certain level of hardness (e.g., PVC or nylon materials), which reduces rolling resistance while applying continuous pressure during rolling to cut flexible materials. However, due to their lower hardness compared to metal blades, they are unsuitable for cutting rigid materials.
Rolling Axle Core
The handle and blade are connected via a smooth axle core, ensuring seamless blade rotation during rolling and preventing material deformation caused by jamming.
