The characteristics of worm gears are the geometry, functional elements and attributes of any object that has been accepted. Through them, we can have a good understanding of the function, behavior and operation of the object.

Strictly speaking: the feature of worm gear is a geometric prototype shape that contains engineering meaning or meaning. The characteristics of worm gears are no longer ordinary voxels here, but a functional element that encapsulates various attributes and functions.

The definition of worm gear features comprehensively reflects the requirements for worm gear features in the three-dimensional modeling design of worm gears and worms. Because the information stored in "worm gear features" includes shape, structure and related attribute information, the scope of coverage includes the underlying geometric information , The functional information of the middle layer and the semantic information of the high-level can meet most of the requirements of each stage of parallel product development. Therefore, the design method oriented to the characteristics of worm gears has become the key technology of 3D parametric modeling.

According to the above analysis, the characteristics of the worm gear are mainly manifested in the following aspects.

(l) The worm gear feature not only has the geometric worm gear feature, but also has the non-geometric worm gear feature. Therefore, the worm gear feature can not only express the geometric information of the parts, but also the non-geometric information of the parts; it can not only express the low-level geometric and topological information, but also express the high-level semantic and functional information, and can also express the overall product shape. Make an abstract description.

(2) The characteristics of worm gears and worms have engineering implications. In different application activities, the forms and connotations of the characteristics of worm gears are often different.

(3) The characteristics of worm gears have operational characteristics such as generation, identification, inheritance, access, abstraction, derivation, mutation, restriction, mapping and extinction.

(4) The feature of worm gear is the key element of using geometric information to model product parts, the "language" for the complete description of product information, the medium of product data exchange, the carrier and basic unit of information transmission between the application links of the integrated system