United States Patent m
Chitayat
[n] 4,392,642 [45] Jul. 12,1983
[54] WORKPIECE POSITIONING TABLE WITH AIR BEARING PADS
[75] Inventor: Anwar Chitayat, Plainview, N.Y.
[73] Assignee: Anorad Corporation, Hauppauge, N.Y.
[21] Appl. No.: 218,930
[22] Filed: Dec. 22, 1980
[51] Int. C1.3 B23Q 1/02
[52] U.S. CI 269/73; 269/285;
269/286; 250/442.1
[58] Field of Search 269/73, 285, 286;
308/3 A, DIG. 1, 9, 5 R, 160; 108/137, 143; 248/424, 429; 33/1 M, 174 L; 250/442, 311;
350/83, 86; 254/89 H; 91/531, 534
[56] References Cited
U.S. PATENT DOCUMENTS
3,289,868 12/1966 Miller et al 254/89 H
3,344,714 10/1967 Hereto 91/534
4,155,173 5/1979 Sprandel 308/DIG. 1
4,227,752 10/1980 Wilcock 308/160
4,234,175 11/1980 Sato et al 269/73
FOREIGN PATENT DOCUMENTS
2238199 2/1974 Fed. Rep. of Germany ... 254/89 H
55-10137 1/1980 Japan 91/531
Primary Examiner—Robert C. Watson
Attorney, Agent, or Firm—Thomas R. Morrison
[57] ABSTRACT
Air bearing pads for supporting a one-axis table in a granite bridge positioning apparatus on a thin film of air include machine-thinned sections for providing resilience to the pads in order to permit flexing sufficient to accommodate surface irregularities on the supporting surface. A single air pressure regulator provides a source of pressurized air to flow-control devices of a plurality of air bearing pads supporting a one-axis table. The individual flow-control devices adjust the flow of air to their respective air bearing pads to individually adjust the lift of the pads.
4 Claims, 5 Drawing Figures
