Page 56 - Modular design for machine tools

Basic Knowledge: What Is the Modular Design? 27

aspect. More specifically, the NC machine tool itself has, in principle, con-
siderable flexibility, which can be realized by only changing the NC
information in accordance with machining requirements; however, in
certain cases, such flexibility has certain limitations. To give certain
remedies to the limited capability of NC software, an enabling techno-
logy is to apply the modular principle to the structural design, which can
be considered as the utmost protruded evidence in phase 2.

Phase 3: 1985 to 2000 and beyond. In phase 3 of the developing history,
a pronounced development of modular design has been realized by apply-
ing it to the FTL, FMS, and FMC. In fact, there are various applications
as follows.
1. In the FMS, the basic module is that of the FMC, compact FMC, or
system machine.
2. In the FMC and system machine, the basic modules are those of unit
and unit complex.

Importantly, not only is the system itself of cell-based modular type, but
also the cell has become popular as exemplified in the growing installa-
tion numbers of FMC within the SME (small-and medium-size enter-
1
prise). In fact, the FMC of flat allocation type approached the compact
FMC of cubic type, i.e., system machine [15], with the advance of flexible
manufacturing. The system machine itself has been more developed to an
advanced kind, i.e., machining complex, as shown in Fig. 1-16. The machin-
ing complex can be characterized by compactly integrating the various
processing functions and enhanced performances within a machine as a
whole. In due course, the system machine and machining complex are
capable of working in stand-alone mode. Without exception, the SMEs are
now very keen to install these new machines instead of the FMC of robot
or pallet pool type shown in Fig. 1-17, which has so far been the most pop-
ular FMC (regarding the detail of phase 3, refer to Chap. 2 ).
Given such a firsthand view of history, some representations will be
reproduced in the following.

1.3.1 Application to TL and FTL
After World War II, the automobile industry was the leading edge within
the industrial nations, especially within the United States in the 1950s.
The United States was requested to lead the world economy, because it

1
The FMC consists of the five basic functions, i.e., those for machining (processing),
transfer, storage, maintenance, and cell controller, and in the FMC of flat allocation type,
all the system hardware is allocated within the two-dimensional space (see Fig. 1-17).