Page 172 - Modular design for machine tools

132 Modular Design Guide and Machine Tools Description

establishing a new classification system. For example, the MC can
machine the die mold with complicated cavity and monolithic parts of
both the aircraft and the computer, resulting in the growing requirement
of more versatile types ever than before. In retrospect, there have been
no trials or proposals for the classification system of the machine tool
since the mid-1960s. With the advent of the NC machine tool, the clas-
sification systems used so far became obsolete, reflecting their poor abil-
ities to cope with the amazing development of machine tools. Obviously,
we have inconvenience in, e.g., the compilation of national statistics for
import and export volumes per kind or type, in which uncertainties are
often included, because of the lack of reliable classification system avail-
able across the whole world. Within this context, Lee et al. proposed a
classification system using the GT code, in which the kernel is to describe
the movement function of MCs [1]. Figure 4-1 reproduces an investigated
result of typology of the MCs on the market, which comprise more than
200 types from about 50 manufacturers. From Fig. 4-1 we can obtain
clearly the important information regarding which type is salable. In
fact, the vertical MC with movement of XY/ZC and horizontal MC with
movement of BX/ZYC or BXZ/YC are very attractive. In addition, clearly
the functional description can contribute to the establishment of a new
classification system to a large extent.
Importantly, a simplified description has been used to classify the
MC of various types by the VDI-Z-Datenbank, where the coordinate
axes used to describe the machine are in accordance with DIN 66217 [2].
In addition, a German manufacturer has claimed the validity of the
functional description to classify the grinding machine, as already shown
in Fig. 1-24, together with justifying the applicability of each variant for
a specified machining requirement [3].
In general, of some methodologies we require the systematic and
rational determination of the new product concept from the strategic
and tactical points of view including the marketability evaluation, and
the functional description provides us with an effective modern tool for
such activity. The MCs of German, Japanese, and Korean make were thus
classified using the functional description, and then their characteristic
features were analyzed, resulting in the obvious comparison of their
competitiveness in the world market [4]. Reportedly, these comparisons
can particularly provide us with some guidelines regarding how to find
the market niche, i.e., given that competition is still sparse in some types
of MC as shown in Fig. 4-2. In addition, it is possible to clarify the market
strategy of each nation from the comparison. For example, we can char-
acterize the German marketing strategy by the following two facets.

1. Together with the manufacture of MCs in fierce competition in the
world market, e.g., X/ZYC type with horizontal single spindle and