Five-Axis Numerical Control Processing Application and Surface Quality Control of HyperMILL-Based Mobile Phone Mold Cavity
The mold cavity structure of mobile phones is one of the most typical complex surface structures. Specific to this type of product, this paper takes some typical product as an example, to conduct Hyper Mill-based analysis and computation for surface processing quality control problem in numerical control milling on the basis of the analysis of traditional mobile phone cavity processing. The description of five-axis processing and path as well as VERICUT simulation is explained with the final application verification. The result shows that the quality control formula of the processing surface is consistent with the actual situation, and the advantages of five-axis processing technology in the application of such types of products are clarified as well.
EQUIVALENT NORMAL CURVATURE APPROACH MILLING MODEL OF MACHINING FREEFORM SURFACES
A new milling methodology with the equivalent normal curvature milling model machining freeform surfaces is proposed based on the normal curvature theorems on differential geometry. Moreover,a specialized whirlwind milling tool and a 5-axis CNC horizontal milling machine are introduced.This new milling model can efficiently enlarge the material removal volume at the tip of the whirlwind milling tool and improve the producing capacity.The machining strategy of this model is to regulate the orientation of the whirlwind milling tool relatively to the principal directions of the workpiece surface at the point of contact,so as to create a full match with collision avoidance between the workpiece surface and the symmetric rotational surface of the milling tool.The practical results show that this new milling model is an effective method in machining complex three- dimensional surfaces.This model has a good improvement on finishing machining time and scallop height in machining the freeform surfaces over other milling processes.Some actual examples for manufacturing the freeform surfaces with this new model are given.
New records of Grania (Clitellata, Enchytraeidae) in the Northeast Atlantic (from Tromsø to the Canary Islands), with descriptions of seven new species
Previous northeast Atlantic records of Grania have been mainly from Germany, southern Scandinavia, and the Atlantic shores of France, Spain and Ireland. They were referred to eight species, with one, G. atlantica, reported from the continental slope. We have examined various unpublished collections from sources spanning from the Canary Islands to the Norwegian Arctic. Apart from new information on morphology, taxonomy, and distribution of known species, we describe seven new taxa (G. canaria, G. fortunata, G. mauretanica, G. aquitana, G. vikinga, G. torosa, and G. papillinasus). The collection of G. papillinasus from 2630-2885 m represents a new depth record for Enchytraeidae. Twenty-five of the now 57 Grania species occur in the North Atlantic. The North Atlantic drift moderates sea temperatures along the northeast Atlantic coasts, probably facilitating the wide latitudinal range of some taxa, as well as actual dispersal within the region. A "chaetal index" (chaetal length : chaetal foot length) is proposed to differentiate L-shaped chaetae at the species level. Complex relationships within the "type 6 group" of Grania suggest that groupings established using certain combinations of penial, chaetal and spermathecal patterns may not be monophyletic. For a better phylogenetic resolution, additional morphological details of these and other characters are needed.