Page 141 - Modular design for machine tools

Engineering Guides and Future Perspectives of Modular Design 101

1. The repeatability of pallet positioning accuracy is better than 2 m.
2. The thermal elongation of the main spindle is 10 m after running
7 h at 1500 rpm rotational speed.
3. The Y axis quill for pallet fixing and traveling is preadjusted and
assembled in consideration of the applied loads in operation.
On the basis of the good reputation of the MA type, Tsugami once
developed a prototype of TC-based system machine, i.e., type TA3 shown
in Fig. 2-23, which can be characterized by its chucking mechanism
and automatic chuck changing; however, it was not on the market.
Modernization of traditional machine tools. With the growing importance
of the system machine, the NC horizontal boring and milling machine
of floor type has been converted to a system machine. All the traverses
are located within the column, and greater machining flexibility due to
the double- or triple-layered main spindle provides the machine with
higher compatibility with flexible manufacturing. Figure 2-24 is such a
machine of Kearns-Richards make in 1990 (boring spindle diameter: 110
or 130 mm), which can also grind the work using the planetary guiding
spindle attached to the facing plate. According to the same idea, Vigel
(Italy) and Steinel (Germany) merchandised a three-layered spindle
and two-layered spindle machine in 1991 and 1994, respectively, in
which the inner spindle has eccentricity to the outer spindle, so that
machining flexibility is enhanced.

Y: Vertical travel

U: Facing slide

Z: Spindle

W: Column travel

X: Longitudinal travel
Figure 2-24 System machine originated from traditional horizontal boring
and milling machine (type F, around 1990, courtesy of Kearns-Richards).