Page 197 - Modular design for machine tools

Application of Machine Tool Description to Engineering Design 157

4.2.2 Variant design for
structural configuration
Apart from the prototype design of a new innovative kind or a design
based on a novel product concept, the machine tool has been manufac-
tured using the variant design. In the variant design, the designer can
use longstanding experience; results of the analytical, achievement,
and acceptance tests; and knowledge obtained from remedies to cope
with the daily improvement and so on to enhance the product quality.
Consequently, the quality of the machine tool is guaranteed to a larger
extent when it is manufactured by the variant design.
Having in mind the beneficial features of the variant design, Shinno
and Ito proposed the generating methods of structural configurations,
in which the possible variants can be produced from the basic structural
pattern. Figure 4-23 shows a basic structural pattern for milling
machine of knee type, and in the variant design, the machine should be
divided into the two subpatterns, i.e., common and variant branches, as

Headstock Z
Flow of force
Spindle
C
X
Y
Table
Y
Column Saddle
X
Knee
Z
Vertical feed screw
Base

Vertical
Head- feed
Spindle stock Column Base screw Knee Saddle Table
C Z X Y

43 0 0 0 0 13 11 12

: Structural modules
: Terminal structural module
Alphabetic symbol : Movement function
Numerals : GT codes to represent
movements
Figure 4-23 Basic structural pattern for milling machine of knee type.