THREE PIECE-COMBINED OIL RING

Title:

THREE PIECE-COMBINED OIL RING

Document Type and Number:

WIPO Patent Application WO/2005/040645

Kind Code:

A1

Abstract:

A three piece-combined oil ring composed of three pieces including axially upper and lower pair of side rails (222) and a spacer expander (224) that is assembled between the side rails and presses the side rails (222) from the inner periphery side to produce tensile forces in the side rails (222). A spacer expander ear section that is made from an austenite stainless steel and that comes in contact with at least a side rail inner surface is subjected to gas nitriding at a temperature not lower than 470°C. This results that a gas nitrided layer having a thickness of 10-60 μm and including a phase having the peak at 2Ѳ = 40º and 2Ѳ = 46º in Cu-K&agr X-ray diffraction is formed. Further, additionally or alternatively, resin coating (31) is applied to those surfaces of the space expander (7) that face at least side-rail side surfaces or to those surfaces of the side rails (5, 6) that face at least the space expander (7).

Inventors:

TAKAHASHI JUNYA (JP)
MURAMATSU GYO (JP)
USUI MIYUKI (JP)

Application Number:

PCT/JP2004/015842

Publication Date:

May 06, 2005

Filing Date:

October 26, 2004

Export Citation:

Click for automatic bibliography generation Help

Assignee:

RIKEN KK (JP)
TAKAHASHI JUNYA (JP)
MURAMATSU GYO (JP)
USUI MIYUKI (JP)

International Classes:

C23C8/26; C23C8/80; C23C28/00; F16J9/06; C21D9/40; (IPC1-7): F16J9/26; C21D1/06; C21D9/40; C23C8/26

Foreign References:

JP2003028299A	2003-01-29
JPH0533866A	1993-02-09
JP2002047554A	2002-02-15
JP2002310299A	2002-10-23
JPH09209830A	1997-08-12
JP2002523689A	2002-07-30
US4407515A	1983-10-04
JP2002047554A	2002-02-15

Other References: