(19)

(11)

EP 0 084 530 A1

(12)

(43) Date of publication: 03.08.1983 Bulletin 1983/31 (21) Application number: 81902200.0 (22) Date of filing: 03.08.1981

(51) International Patent Classification (IPC):  E21C 35/ 20( . ) E21C 35/ 24( . ) (86) International application number: PCT/US1981/001030 (87) International publication number: WO 1983/000525 (17.02.1983 Gazette 1983/05)

(84) Designated Contracting States: AT CH DE FR GB LI LU NL SE (60) Divisional application: 85109312.0 / 0172438 (71) Applicant: VIDEO MINERS, INC. Woodland, PA 16881 (US)	(72) Inventors: LANSBERRY, John B. Woodland, PA 16881 (US) APT, Jerome, Jr. Pittsburgh, PA 16881 (US) DURY, Joseph D., Jr. Sewickley, PA 15143 (US) (74) Representative: KUHNEN, WACKER & PARTNER  Alois-Steinecker-Strasse 22 D-85354 Freising D-85354 Freising (DE)