| Nippon Piston Ring Co., Ltd. Patent applications |
| Patent application number | Title | Published |
|---|
| 20120061920 | OIL RING MECHANISM OF A PISTON - An oil ring mechanism of a piston includes a circumferential ring groove formed in an outer peripheral surface of the piston, and a two-piece oil ring having a ring-shaped ring main body that is arranged in the ring groove and urged in the outer peripheral direction inside the ring groove by a coil expander arranged on the inner peripheral side of the oil ring main body. On lower side surface on a crankcase side of a side wall surface of the ring groove that is on the opposite side of the ring groove from an engine combustion chamber, first and second recessed portions that reduce the abutment area where a lower surface of the ring main body abuts against the lower side surface formed in a lower side abutment surface that serves as a surface for abutting against the lower surface of the ring main body. | 03-15-2012 |
| 20110023808 | IRON-BASED SINTERED ALLOY FOR VALVE SEAT, AND VALVE SEAT FOR INTERNAL COMBUSTION ENGINE - It is an object of the present invention to provide a valve seat product in which the amount of hard particles added to improve the wear resistance of a valve seat of an internal combustion engine is increased, and is excellent in the mechanical strength and machinability. In order to achieve the object, an iron-based sintered alloy material for a valve seat is employed which is made to contain a first hard particle having an average primary particle diameter of 5 to 20 μm and a second hard particle having an average primary particle diameter of 20 to 150 μm in a texture, wherein a particle size distribution curve measured by laser diffraction scattering analysis has N peaks (N is an integer equal to or larger than 2) and when particle diameters corresponding to the peak top positions are denoted as D | 02-03-2011 |
| 20100319647 | COMBINATION STRUCTURE OF PISTON RING AND CYLINDER LINER FOR INTERNAL COMBUSTION ENGINE - An object of the present invention is to provide a cylinder structure reduced in mutual damage caused by a sliding operation of a piston ring and a cylinder liner when the piston ring having a linear expansion property which follows linear expansion of the cylinder liner made of an aluminum alloy is used. In order to achieve the object, a combination structure of the piston ring and the cylinder liner for an internal combustion engine described below is employed. In the cylinder liner for an internal combustion engine, the inner circumferential surface satisfies the conditions, a ten-point height of roughness profile (Rz | 12-23-2010 |
| 20100253006 | STEEL PRODUCTS FOR PISTON RINGS AND PISTON RINGS - A steel product having a composition which contains by mass C: 0.01 to 1.9%, Si: 0.01 to 1.9%, Mn: 5.0 to 24.0% with balance consisting of Fe and unavoidable impurities and a steel product described above which further contains Cr: 18.0% or below and/or Ni: 12.0% or below in addition to the above essential elements. The above steel products may each further contain Al: 1% or below and/or N: 0.3% or below and the above steel products may each further contain one or more elements selected from among Nb, Ti, Zr, Mo and Cu in a total amount of 4.0% or below. The steel products can sufficiently follow the thermal expansion of a cylinder made of an aluminum alloy and thus enables the production of a piston ring which is suitable for use as a piston ring to slide on the inner face of a cylinder bore made of an aluminum alloy in an internal combustion engine and which can retain excellent sealing properties. | 10-07-2010 |
| 20100239451 | Flake Graphite Cast Iron And Production Method Thereof - The invention provides a flake graphite cast iron being highly strong and excellent in workability such as cutting performance, which is suitable for use, for example, in internal combustion engine parts and the like, and a production method thereof without using a misch metal. Specifically, the flake graphite cast iron according to the invention includes an A-type graphite with a uniformly and disorderly distributed existence form without directionality; and has a chemical composition containing 2.8 to 4.0 mass % of C, 1.2 to 3.0 mass % of Si, 1.1 to 3.0 mass % of Mn, 0.01 to 0.6 mass % of P, 0.01 to 0.30 mass % of S and the remainder being Fe and inevitable impurities, wherein the ratio (Mn/S) of the Mn content to the S content is within a range of 3 to 300. | 09-23-2010 |
| 20100224146 | METHOD FOR MANUFACTURING A SHAFT MEMBER HAVING A SINTERED PART BONDED THERETO AND A CAMSHAFT FOR AN INTERNAL COMBUSTION ENGINE - A method for manufacturing a shaft member having a sintered part bonded thereto is simple and provides an increased process yield and a high accuracy in position and angle of the sintered part. A green compact is prepared by subjecting a metal or alloy powder to a compression molding. A projection formed on an outer peripheral surface of the shaft member is embedded into the green compact, while chipping partially the green compact with the projection, to combine the green compact with the shaft member. Then, a sintering is carried out. | 09-09-2010 |
| 20090058014 | PISTON RING - There is provided a piston ring which can effectively prevent aluminum adhesion phenomenon to the piston ring. The piston ring includes a piston ring main body and a surface coating film on either upper or lower surface of the piston ring main body, or both the upper and lower surfaces of the piston ring. The surface coating film includes heat-resistant resin and copper based powder contained therein. | 03-05-2009 |
| 20090051123 | PISTON RING - A piston ring includes a piston ring body and a surface coating film formed on at least one of upper and lower surfaces of the piston ring body. The surface coating film has a most outside surface layer including a heat-resistant resin and a metal powder contained in the heat-resistant resin and a base bottom layer formed nearest the piston ring body and including a heat-resistant resin. The base bottom layer may also include a metal powder. | 02-26-2009 |
| 20090051122 | PISTON RING - A piston ring includes a piston ring body and a surface coating film formed on at least one of upper and lower surfaces of the piston ring body. The surface coating film comprises a heat-resistant resin and a metal powder contained in the heat-resistant resin, and a phosphate coating film is formed, as base coating film of the surface coating film, on a surface on which the surface coating film of the piston ring body is formed. | 02-26-2009 |
| 20090026711 | COMPRESSION PISTON RING - A generally circular compression piston ring having an outer peripheral surface, an inner peripheral surface, and a pair of end faces splitting the circular shape in a radial direction thereof for defining a gap portion. The ring has a first portion including a notched portion formed at the inner peripheral surface and extending over a predetermined circumferential length portion starting from the end face, and a second portion other than the first portion. The second portion has a radial thickness ranging from 2.0 mm to 6.0 mm. The notched portion is a plane shape gradually reaching the outer peripheral surface toward the end face. The end face has a radial thickness ranging from 0.2 times to less than 0.5 times as large as the radial thickness of the second portion. The outer peripheral surface defines a center serving as a center of a center angle, and the predetermined circumferential length portion is defined by the center angle ranging from 26.5 degrees to 14 degrees. | 01-29-2009 |
| 20090013866 | THREE-PIECE OIL RING AND COMBINATION OF THE THREE-PIECE OIL RING AND PISTON - A three-piece oil ring and a combination of the three-piece oil ring and a piston, those capable of realizing improved sealing property and reduction in lubrication oil consumption with avoiding generation of sticking even at low tension and thin width of the ring. The three-piece oil ring includes a spacer expander | 01-15-2009 |
