Page 88 - Modular design for machine tools

54 Modular Design Guide and Machine Tools Description

Within a grinding machine context, the NC machine was belatedly on
the market, and thus the GC itself and the transfer grinding line were
contrived in the late 1980s. This backwardness is caused by the require-
ment for higher machining accuracy in grinding than in cutting. For
example, Yamazaki Mazak merchandised the GC in the beginning of the
1990s on the basis of the TC. The GC in the 1990s can be classified into
(1) TC-based and (2) MC-based types, and furthermore (3) turret column
type, in which the grinding wheel can be exchanged by indexing the
column. In due course, both the GCs based on TC and MC are dominant,
and in these GCs, the basic necessity is to provide the adaptive control
function, continuous truing and dressing device of between-process type,
tool changer. and so on. In the tool changer, the ATC for cutting tools is
apparently replaced to that for grinding wheels, although the tapered
shank to mount the grinding wheel to the spindle is in contact at both
the side surface of flange and the tapered surface.
On the extension of the TC, MC, and primitive GC, the system
machine and machining complex have been contrived as their advanced
kinds in the mid-1980s and later, respectively. The system machine can
be interpreted as a cubiclike compact FMC to reduce the floor space,
simultaneously maintaining the function and performance of the FMC.
As already clarified elsewhere, the capability of FMC can be compared
to that of FMS, and thus the SME has been very keen to install the FMC,
because the SME faces, in general, the acute shortage of factory space.
In this context, the system machine is one of the further solutions for
facing such a problem of SME together with responding to the various
machining requirements. In contrast to the conventional and advanced
NC machine tools, the advent of system machine and machining com-
plex has thus evoked the growing importance of the modular design
once again. It is very interesting that the system machine is typical
evidence for “Developing trajectory of a technology being ‘Divergence and
Convergence’ processes” in engineering field (see Chap. 2).

1.3.4 Different-kind generating
modular design
This concept is considered to be modular design by birth, and machine
tools of various kinds can, in principle, be manufactured from a group
of modules, where the module is in the form of a unit. For example, a
group of units facilitates the manufacture of the drilling, milling, and
turning machines as already shown in Fig. 1-10, which was displayed
by Koenigsberger in 1974 [7, 10].
On that occasion, Koenigsberger stated that there was no practical evi-
dence of this modular design concept and that the due research was
being conducted by the UMIST (University of Manchester Institute of