Patents Assigned to Nippon Piston Ring Co., Ltd.
  • Patent number: 10087513
    Abstract: A piston ring having a hard carbon film formed on at least an external peripheral sliding surface of a piston ring base material, the hard carbon film having an sp2 component ratio within a range of 40% to 80% inclusive as measured by a TEM-EELS spectrum which combines electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), a hydrogen content being in a range of 0.1 at. % to 5 at. % inclusive, and an amount of macroparticles appearing on the surface being within a range of 0.1% to 10% inclusive by area ratio. The hard carbon film is formed on a hard carbon foundation film formed under low-speed film-forming conditions on the side of the piston ring base material, and the hard carbon foundation film is formed with an arc current value 80% or less of the arc current value during the formation of the hard carbon film.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: October 2, 2018
    Assignee: NIPPON PISTON RING CO., LTD
    Inventors: Takuya Ozaki, Hiroyuki Sugiura
  • Patent number: 10030772
    Abstract: A multi-piece oil ring includes an oil ring main member in which two rails are connected together by a columnar part and which has a roughly I-shaped cross section; and a coil expander disposed in an inner circumferential groove formed on the inner circumferential surface of the columnar. Each rail in the oil ring main member possesses a sliding section protuberance whose tip possesses a jutting portion. The axial length of the jutting portion is 0.02-0.18 mm. The change rate of the axial length of the individual jutting portion is in the range of 0 to 80% at least in a region of from its sliding surface to be faced to a cylinder, which is positioned at the tip of the jutting portion, to a position of 0.03 mm away from the aforementioned sliding surface in the radial direction of the oil ring main member.
    Type: Grant
    Filed: March 26, 2010
    Date of Patent: July 24, 2018
    Assignee: NIPPON PISTON RING CO., LTD.
    Inventors: Atsushi Chiba, Kazuhiro Fujimura, Iwao Hiraishi, Makoto Kajiwara
  • Publication number: 20180180181
    Abstract: To provide a piston ring comprising a hard carbon film that is easy to form and exhibits excellent adhesion and wear resistance, and a manufacturing method therefor. The above-described problem is solved by means of a piston ring comprising a hard carbon film 50 formed on at least an outer peripheral sliding surface 11 of a piston ring base material 1, wherein the hard carbon film 50 is a laminated film comprising a plurality of layers, including an upper layer 5 with a lamination pitch within a range of 3 nm to 50 nm inclusive, a middle layer 4 with a lamination pitch less than that of the upper layer 5, and a lower layer 3 with a lamination pitch within the same range as that of the upper layer 5 and greater than that of the middle layer 4.
    Type: Application
    Filed: July 29, 2016
    Publication date: June 28, 2018
    Applicant: NIPPON PISTON RING CO., LTD.
    Inventors: Takuya OZAKI, Hiroyuki SUGIURA
  • Publication number: 20180180182
    Abstract: To provide a piston ring comprising a hard carbon film that is easy to form and exhibits excellent wear resistance. The above-described problem is solved by having a hard carbon film 4 formed on at least an outer peripheral sliding surface 11 of a piston ring base material 1, wherein the hard carbon film 4 is a laminated film comprising a plurality of layers, and is configured so as to contain boron within a range of an atomic density of 0.2×1022 atoms/cm3 to 2.0×1022 atoms/cm3 inclusive. This hard carbon film 4 may be configured to have an sp2 component ratio within a range of 40% to 80% inclusive, measured in a TEM-EELS spectrum formed by combining electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), and a hydrogen content within a range of 0.1 atom % to 5 atom % inclusive. Further, a total thickness of this hard carbon film 4 may be configured to be within a range of 0.5 ?m to 20 ?m inclusive.
    Type: Application
    Filed: July 29, 2016
    Publication date: June 28, 2018
    Applicant: NIPPON PISTON RING CO., LTD.
    Inventors: Takuya OZAKI, Hiroyuki SUGIURA
  • Publication number: 20180051806
    Abstract: A combined oil ring in which carbon sludge and the like are not deposited between side rails and a spacer expander even if an internal combustion engine is operated for a long period of time. The combined oil ring includes an outer circumferential end portion of a space forming part and a continuous part that are closed and not open toward the outer circumferential side, thereby reducing carbon sludge deposits.
    Type: Application
    Filed: March 31, 2016
    Publication date: February 22, 2018
    Applicant: NIPPON PISTON RING CO., LTD
    Inventors: Yasuyuki MURATA, Kenji ARAI, Ryosuke KAMATA, Hideshi HITOSUGI, Kazutomo TAKAHASHI, Toru TSUKUI
  • Patent number: 9882442
    Abstract: An axial gap type rotating electric machine, having a stator with first tooth parts protruding in an axial direction and formed in a concentric arc-like manner, and a rotor with magnetic poles arranged in a distributed manner in the circumferential direction, and the magnetic poles include second tooth parts that protrude in the axial direction and are formed in a concentric arc-like manner, the second tooth parts being opposedly arranged so as to respectively engage with the first tooth parts with the intermediation of the air gap. The rotor is incorporated in the rotating member so as to be movable in the axial direction and so as not to be rotatable with respect to the rotating member. The rotating electric machine further includes an urging device that makes the air gap between the rotor and the stator adjustable.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: January 30, 2018
    Assignee: NIPPON PISTON RING CO., LTD
    Inventors: Masafumi Sakamoto, Shigeyoshi Sato, Shunsuke Takeguchi, Shun Yasuda
  • Patent number: 9863534
    Abstract: A piston ring having a hard carbon coating film is provided that can be easily formed in the same batch, does not cause delamination, and is excellent in initial running-in and wear resistance. A hard carbon coating film is formed at least on an outer peripheral sliding surface of a piston ring base and contains substantially no hydrogen, wherein the hard carbon coating film has an sp2 content ratio ranging from 40% to 80% measured in a TEM-EELS spectrum where transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) are combined together, and an area ratio of contained macro particles on a surface of the hard carbon coating film ranges from 0.1% to 10.0%.
    Type: Grant
    Filed: February 27, 2014
    Date of Patent: January 9, 2018
    Assignee: NIPPON PISTON RING CO., LTD.
    Inventors: Takuya Ozaki, Hiroyuki Sugiura
  • Patent number: 9803268
    Abstract: An iron-base sintered alloy material includes a matrix phase, Co base inter-metallic compound particles having hardness of 600 to 1200 HV, carbide-type particles having hardness of 400 to 700 HV, and optionally solid-lubricant particles, the particles being dispersed in the matrix phase. A matrix part including the matrix phase and the two kinds of hard-particles contains 0.3 to 1.5% by mass of C, and 10 to 50% by mass of one or more kinds selected from Si, Mo, Cr, Ni, Co, Mn, S, N, V, Ca, F, Mg, and O, the balance being Fe and unavoidable impurities. By dispersing, in the matrix phase, the Co base inter-metallic compound particles having high hardness, and the carbide-type particles having low hardness and low aggressiveness to mated material and increasing mechanical strength, wear-resistance can be improved with low aggressiveness to mated material and high radial crushing strength (350 MPa or more).
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: October 31, 2017
    Assignee: NIPPON PISTON RING CO., LTD.
    Inventors: Hiroshi Oshige, Satoshi Ikemi
  • Publication number: 20170306257
    Abstract: Provided are a coating film, a manufacturing method for the same, and a PVD device that not only sufficiently improve the balance of low-friction properties and wear resistance, but also improve chipping resistance and peeling resistance. This film is coated on a substrate surface, wherein the coating film has a hard carbon that presents relatively black and white when observed in a cross-sectional bright-field TEM image, a mesh-shaped hard carbon layer is formed using a PVD method, said layer having white-colored hard carbon in a mesh shape extending in the thickness direction and black-colored hard carbon dispersed into the cavities in the mesh, and the ID/IG ratio is 1-6 when the mesh-shaped hard carbon layer is measured using Raman spectroscopy, said ratio being the ratio of the Raman spectrum D band peak area intensity and G band peak area intensity.
    Type: Application
    Filed: September 17, 2014
    Publication date: October 26, 2017
    Applicants: NIPPON ITF, INC., NIPPON PISTON RING CO., LTD.
    Inventors: Hideki MORIGUCHI, Tadashi SAITO, Yoshikazu TANAKA, Akinori SHIBATA, Tetsumi ARAHI, Katsuaki OGAWA, Takahiro OKAZAKI, Hiroyuki SUGIURA, Yoshihiro ITO
  • Publication number: 20170283935
    Abstract: Provided are a coating film, a manufacturing method for the same, and a PVD device that not only sufficiently improve the balance of low-friction properties and wear resistance, but also improve chipping resistance (defect resistance) and peeling resistance. This coating film coats a substrate surface, wherein a hard carbon layer is formed extending in columns-shape perpendicular to the substrate when observed in a cross-sectional bright-field TEM image, the hard carbon layer is formed using a PVD method, and the ID/IG ratio is 1-6 when the hard carbon layer is measured using Raman spectroscopy, said ratio being the ratio of the Raman spectrum D band peak area intensity and G band peak area intensity.
    Type: Application
    Filed: September 17, 2014
    Publication date: October 5, 2017
    Applicants: NIPPON ITF, INC., NIPPON PISTON RING CO., LTD.
    Inventors: Hideki MORIGUCHI, Tadashi SAITO, Yoshikazu TANAKA, Tetsumi ARAHI, Katsuaki OGAWA, Takahiro OKAZAKI, Hiroyuki SUGIURA, Yoshihiro ITO
  • Patent number: 9752214
    Abstract: A titanium alloy includes 15 to 27 atomic % (at %) of tantalum (Ta) and 0 to 8 at % of tin (Sn), the balance being titanium (Ti) and unavoidable impurities, when the entire amount of the titanium alloy is taken as 100 at %. Therefore, the titanium alloy provided has characteristics suitable for medical device materials, biocompatible materials, etc.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: September 5, 2017
    Assignees: NIPPON PISTON RING CO., LTD., NATIONAL UNIVERSITY CORPORATION SAITAMA UNIVERSITY
    Inventors: Shunsuke Takeguchi, Yoshiki Ishikawa, Takasumi Kubo, Shin Ishida, Hiroki Takahashi, Masafumi Morita, Masahito Miki
  • Publication number: 20170227126
    Abstract: Provided is a combined oil ring that further reduces engine oil consumption. A combined oil ring attached to an oil ring groove of a piston includes: a pair of upper and lower side rails each formed into a flat annular shape, and having a slide contact part that comes into sliding contact with a cylinder; and a spacer expander arranged between the pair of upper and lower side rails. In at least the upper side rail of the pair of upper and lower side rails, a cross-sectional shape of the slide contact part along an axial direction of the piston is a tapered shape linearly spreading from upper to lower parts of the piston; the tapered shape is at an angle of 5 to 30 degrees with respect to a central axis of the spacer expander, and has a vertex of the tapered shape within 0.15 mm from a lower end of the side rail; and a part closer to the lower end than the vertex is formed into a curved shape having a curvature of R0.01 to 0.5.
    Type: Application
    Filed: July 22, 2015
    Publication date: August 10, 2017
    Applicant: NIPPON PISTON RING CO., LTD.
    Inventors: Masataka KAWASAKI, Mamoru MIYAMOTO, Hideshi HITOSUGI, Kenji ARAI
  • Publication number: 20170167609
    Abstract: Provided is a piston ring (10) comprising a sliding surface (11) covered with a Cr—B—V—N alloy film (3), wherein a B content is within a range of 0.1-1.5 mass % inclusive, a V content is within a range of 0.05-1 mass % inclusive, and a ratio [B content/V content] is within a range greater than 1 and 30 or less, thereby achieving a piston ring (10) having higher wear resistance, cracking resistance, and peeling resistance. This alloy film (3) preferably further includes Ti, the Ti content being within a range greater than 0 mass % and 8 mass % or less. Such a piston ring (10) is preferably mounted on an engine that uses an alcohol fuel or an alcohol-containing fuel.
    Type: Application
    Filed: June 30, 2015
    Publication date: June 15, 2017
    Applicant: NIPPON PISTON RING CO., LTD
    Inventors: Noriaki CHIDA, Masataka OKANO
  • Publication number: 20170002454
    Abstract: A piston ring having a hard carbon film formed on at least an external peripheral sliding surface of a piston ring base material, the hard carbon film having an sp2 component ratio within a range of 40% to 80% inclusive as measured by a TEM-EELS spectrum which combines electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), a hydrogen content being in a range of 0.1 at. % to 5 at. % inclusive, and an amount of macroparticles appearing on the surface being within a range of 0.1% to 10% inclusive by area ratio. The hard carbon film is formed on a hard carbon foundation film formed under low-speed film-forming conditions on the side of the piston ring base material, and the hard carbon foundation film is formed with an arc current value 80% or less of the arc current value during the formation of the hard carbon film.
    Type: Application
    Filed: January 30, 2015
    Publication date: January 5, 2017
    Applicant: NIPPON PISTON RING CO., LTD
    Inventors: Takuya OZAKI, Hiroyuki SUGIURA
  • Patent number: 9528606
    Abstract: A combined oil ring that reduces deposits between side rails and a spacer expander there between. The spacer expander includes: upper pieces and lower pieces that are alternately arranged in a circumferential direction to be spaced apart in an axial direction and the circumferential direction; coupling pieces that respectively couple the adjacent upper and lower pieces; and ear parts that erect in an inner circumferential end portion of the upper and lower pieces and push the side rails. At least one of an upper surface of each upper piece and a lower surface of each lower piece has a groove formed thereon. Ear parts have a through-hole with which the groove is communicated and a distance along the axial direction between an upper or lower surface of each ear part at a top thereof and a deepest portion of the groove is at least 0.22 mm.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: December 27, 2016
    Assignee: NIPPON PISTON RING CO., LTD
    Inventors: Hideshi Hitosugi, Kenji Arai, Kazutomo Takahashi
  • Patent number: 9506138
    Abstract: The second compression ring is formed such that the outer peripheral surface shape has a tapered face, and the radial cross-sectional shape is a rectangular ring, a scraper ring, or a Napier ring, and has a piston ring base and a hard film provided at least on an outer peripheral sliding surface thereof. The piston ring base is composed of a low-alloy steel or carbon steel having a Vickers hardness of Hv 350 Hv 550. The outer peripheral sliding surface is formed so that the axial length is from 0.01 to 0.30 mm between the outer edge end part of the tapered outer peripheral sliding surface and an imaginary line contacting with a lower end surface where a curved surface having a diameter that decreases gradually inward from the outer edge end part toward the lower end in the axial direction is parallel to a ring underside.
    Type: Grant
    Filed: April 23, 2015
    Date of Patent: November 29, 2016
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Hiroyuki Sugiura, Atsushi Chiba, Makoto Kajiwara, Kazuhiro Fujimura, Katsuaki Ogawa, Kazuhiro Sameshima
  • Patent number: 9464717
    Abstract: Provided is a piston ring such that it is possible to sufficiently inhibit adhesive wear when the piston ring is mounted to a piston for a diesel engine in which at least the piston ring groove in the piston is formed from steel or cast iron. Disclosed is a piston ring mounted to a piston for a diesel engine, wherein the load length ratio (Rmr2) (in accordance with JIS B0601:2001) of the top surface and bottom surface of the piston ring satisfies each of the following conditions: Rmr2 (0.5%, 0.3[mu]m)=20% and Rmr2 (0.5%, 0.4[mu]m)=40%.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: October 11, 2016
    Assignee: NIPPON PISTON RING CO., LTD.
    Inventors: Michihiro Ito, Naoyuki Akimoto, Iwao Hiraishi, Makoto Kajiwara, Atsushi Chiba
  • Publication number: 20160003356
    Abstract: A piston ring having a hard carbon coating film is provided that can be easily formed in the same batch, does not cause delamination, and is excellent in initial running-in and wear resistance. A hard carbon coating film is formed at least on an outer peripheral sliding surface of a piston ring base and contains substantially no hydrogen, wherein the hard carbon coating film has an sp2 content ratio ranging from 40% to 80% measured in a TEM-EELS spectrum where transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) are combined together, and an area ratio of contained macro particles on a surface of the hard carbon coating film ranges from 0.1% to 10.0%.
    Type: Application
    Filed: February 27, 2014
    Publication date: January 7, 2016
    Applicant: NIPPON PISTON RING CO., LTD.
    Inventors: Takuya OZAKI, Hiroyuki SUGIURA
  • Publication number: 20150369090
    Abstract: A highly wear-resistant valve seat insert is provided. When an iron-based powder, a hard-particle powder, and a graphite powder are mixed to obtain a mixed powder, for formation of a layer on a valve-contacting face side, the hard-particle powder having an average particle size 15-50 ?m, and the iron-based powder having an average particle size 15-50 ?m are blended so a matrix part composition after sintering is a composition containing C: 0.3 to 2.0% by mass, one or more kinds selected from Co, Si, Ni, Mo, Cr, Mn, S, W, and V at 70% by mass or less in total, the balance being Fe and unavoidable impurities and a matrix part structure after sintering is a structure which contains hard-particles at from 10 to 65% by mass with respect to a total amount of a layer on a valve-contacting face side and disperses the hard-particles at 1000 particles/mm2 or more.
    Type: Application
    Filed: January 31, 2014
    Publication date: December 24, 2015
    Applicant: NIPPON PISTON RING CO., LTD.
    Inventors: Satoshi IKEMI, Hiroshi OSHIGE, Kenichi SATO
  • Publication number: 20150214797
    Abstract: An axial gap type rotating electric machine including a stator that includes m salient poles that protrude from a discoid magnetic material in a rotating shaft direction and are arranged in a circumferential direction. A winding wire is wound around an outer periphery of each of the salient poles. The rotor includes n permanent magnet poles and n rotor magnetic materials that are alternately arranged in the circumferential direction. The permanent magnet poles each include a magnet pole piece and a permanent magnet that are fixedly attached to each other and arranged in an axial direction, the magnet pole piece being made of a magnetic material. A plurality of teeth are formed in a concentric arc-like manner in an opposing part between: the magnet pole pieces and the rotor magnetic materials; and the stator so as to engage with each other with the intermediation of the air gap.
    Type: Application
    Filed: January 22, 2015
    Publication date: July 30, 2015
    Applicant: NIPPON PISTON RING CO., LTD
    Inventors: Masafumi SAKAMOTO, Shigeyoshi SATO, Shunsuke TAKEGUCHI