Modular power-driven rotary knife, improved handle and method

Abstract

A modular power-driven knife having an annular rotary blade, the structure of which knife can be varied through choice of standardized, i.e., compatible, components to accommodate different operators and different tasks. The components include plural elongated handles to accommodate different sized hands; plural headpieces, each having a transmission for driving an annular rotary blade and identical means by which any of the handles are attachable in a first orientation, and each differently constructed to support a replaceable blade housing of predetermined size and construction different from housings supported by other headpieces, including a construction for angling the blade housing and blade relative to the extending handle; adjustable thumb supporting pieces for the handles; handle adapters to reposition the handles; pistol grip handles; drive cable casing connectors; and replaceable blade housings securable to the headpieces for supporting replaceable rotary annular blades. The modular construction is designed to allow adjustment between or among parts to accommodate different physiologies of users and different modes of use and different tasks for which the assembled knife may be used. The handles provided for the modular knife are of improved shape that reduces unwanted areas of pressure concentration on the gripping hand while at the same time providing as firm a grip as possible for a given gripping force. A method of selecting the proper handle size is provided.