A PISTON CONSTRUCTION FOR AN AXIAL BEARING OF A DRILLING MACHINE

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EP 0 868 263 A1

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(43)	Date of publication:
	07.10.1998 Bulletin 1998/41

(21)	Application number: 96933451.0

(22)	Date of filing: 09.10.1996

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International Patent Classification (IPC):

B25D 9/ 26^{( . )}
B25D 17/ 24^{( . )}
E21B 1/ 26^{( . )}

B25D 9/ 14^{( . )}
E21B 1/ 00^{( . )}

(86)	International application number:
	PCT/FI1996/000529

(87)	International publication number:
	WO 1997/013622 (17.04.1997 Gazette 1997/17)

(84)	Designated Contracting States:
	DE FR GB SE

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Priority:

10.10.1995 FI 19950004822

(71)	Applicant: TAMROCK OY
	33100 Tampere (FI)

(72)	Inventor:
	MUUTTONEN, Timo FIN-37200 Siuro (FI)

(74)	Representative: Kaukonen, Juha Veikko, et al
	Kolster Oy Ab, Iso Roobertinkatu 23, P.O. Box 148 00121 Helsinki 00121 Helsinki (FI)

(54)	A PISTON CONSTRUCTION FOR AN AXIAL BEARING OF A DRILLING MACHINE