Relationship Between Handle Size of Milling Machine and Comfortableness to Handle Operation.

In order to clarify the relationship between handle size of milling machine and comfortableness to handle operation, sensory evaluation test and the measurement of cutting force and contact pattern between hand and handle have been performed. It was proved that the handles of larger sizes were evaluated as more comfortable, the subjects operating large handle with both hands could operate with large cutting force and short operation time, and the subjects operating handle with one hand could not rotate continuously the handle. It was thought that the comfortableness to handle operation depends on the large contact area between hand and handle and small load on hand.