Page 198 - Modular design for machine tools

158 Modular Design Guide and Machine Tools Description

shown in Fig. 4-24(a). In general, the machining space corresponds with
the variant branch, and then the movement functions at the variant
branch are reallocated considering possible combinations of the structural
unit [18]. In an actual case, such combinations are stored in the computer
in the form of a pair of units, which can be chosen through the evalua-
tion of its relative movement and dynamic performance. Figure 4-24(b)
shows some variants produced from the basic pattern.
In contrast to a simple variant design mentioned above, Shinno and
Ito proposed another variant design for structural configuration using

Variant part

Mainflow of force

Subflow of force

Common part
C Z X Y

Variant part in Variant part in
the mainflow Common part the subflow

(a)

X

Y Y
C
X C
C Y X

Z Z Z

(b)
Figure 4-24 Variant design method and its application to milling machine of knee
type: (a) Idea of variant design and (b) some examples of variants produced.