Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
CYLINDER
Document Type and Number:
Japanese Patent JP2010236443
Kind Code:
A
Abstract:

To provide a cylinder reducing reciprocating friction with a piston, and avoiding longitudinal scratch and excessive friction that possibly occur between a piston skirt portion and a cylinder.

In a stroke central part region which is a region ranging from a lower surface position of a ring groove of a lowermost piston ring in a top dead center of the piston, to an upper surface position of a ring groove of an uppermost piston ring in a bottom dead center of the piston, a plurality of recessed portions are formed so that at least one recessed portion in all cross-sections in a circumferential direction of cylinder exists, and the recessed portion is not formed in a region except for the stroke central region, out of inner wall surfaces of the cylinder. A total of areas of all recessed portions is to be within a range of 1 to 80%, when an area of the stroke central region is assumed to be 100%. Out of a region that slides with a piston skirt at a thrust side of the piston used in combination with the cylinder, in the stroke central region, at least 1/4 or more thereof is to be a region where the recessed portion is not formed.

COPYRIGHT: (C)2011,JPO&INPIT


Inventors:
URABE MITSURU
MURATA TAIICHI
Application Number:
JP2009086288A
Publication Date:
October 21, 2010
Filing Date:
March 31, 2009
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
NIPPON PISTON RING CO LTD
International Classes:
F02F1/00; F16J1/04; F16J10/04
Domestic Patent References:
JP2007132247A2007-05-31
JP2005090442A2005-04-07
JP2007002989A2007-01-11
JP2002235852A2002-08-23
JPS6158656U1986-04-19
JPS6259743U1987-04-14
Foreign References:
WO2009044824A12009-04-09
Attorney, Agent or Firm:
Yasuo Ishikawa
Yoshinori Ishibashi