Patents Assigned to Kabushiki Kaisha Riken
  • Piston ring
    Patent number: 9709169
    Abstract: A piston ring having a resin-based film covering at least one of the upper and lower sides, wherein the resin-based film contains a fibrous filler with a mean fiber diameter of 50 to 500 nm and an aspect ratio of 30 to 500, wherein the fibrous filler in the resin-based film to align roughly parallel to the film surface.
    Type: Grant
    Filed: October 29, 2012
    Date of Patent: July 18, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Toshikatsu Hayashi, Kouhei Sugimoto, Yoshinari Watanabe, Hayato Sasaki
  • Piston ring sprayed coating, piston ring, and method for producing piston ring sprayed coating
    Patent number: 9664281
    Abstract: A thermal spray coating for piston ring having excellent abrasion resistance, and capable of suppressing abrasion of the opposite member is provided. The thermal spray coating for piston ring according to the invention is a thermal spray coating for piston ring obtained by thermally spraying a powder composition on the outer peripheral sliding surface of a piston ring base material, and the powder composition contains molybdenum particles, nickel chromium alloy particles and chromium carbide particles, and the median diameter of the chromium carbide particles is 5 to 25 ?m.
    Type: Grant
    Filed: October 29, 2013
    Date of Patent: May 30, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Shuichi Kamura, Kazuhiko Hirota
  • SINTERED VALVE SEAT AND ITS PRODUCTION METHOD
    Publication number: 20170145875
    Abstract: To provide a press-fit, sintered valve seat having high valve coolability and wear resistance for use in a high-efficiency engine, and its production method, Cu powder having an average particle size of 45 ?m or less and purity of 99.5% or more is used to form a network-connected Cu matrix, even though a relatively large amount of hard Co-based alloy particles are added; and Fe—P alloy powder is used for densification by liquid-phase sintering.
    Type: Application
    Filed: June 17, 2015
    Publication date: May 25, 2017
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventor: Kimiaki HASHIMOTO
  • Combined oil control ring
    Patent number: 9657838
    Abstract: A combined oil control ring for automobile engines capable of keeping an excellent oil-controlling function without suffering sticking between a spacer expander and side rails for a long period of operation comprises upper and lower two side rails, and an axially corrugated spacer expander having upper and lower portions; a leg portion connecting each upper portion and each lower portion of the spacer expander having a portion having an inclination angle ? of 15° or more from the axial direction.
    Type: Grant
    Filed: May 27, 2013
    Date of Patent: May 23, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventor: Yoshihito Ooya
  • PISTON RING FOR INTERNAL COMBUSTION ENGINE
    Publication number: 20170138476
    Abstract: Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ring 1 for the internal combustion engine including a piston ring body 11 having at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film 12, wherein the aluminum cohesion resistance film 12 has a first coating film 12a made of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film 12a.
    Type: Application
    Filed: October 16, 2014
    Publication date: May 18, 2017
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Hayato SASAKI, Takashi ONO, Yongtie YAN
  • Combination of cylinder and piston ring
    Patent number: 9644738
    Abstract: To provide a combination of a cylinder made of a hypereutectic Al—Si alloy and a hard-carbon-coated piston ring both exhibiting excellent wear resistance, the piston ring is provided with a laminate coating at least on an outer peripheral sliding surface thereof; the laminate coating comprising a metal layer, a metal-containing, hard carbon layer, and a metal-free, hard carbon layer in this order from the substrate side; the laminate coating having Martens' hardness (indentation hardness) HMs of 5-13 GPa, indentation modulus E of 70-200 GPa, and a deformation ratio Rpe of 0.45 or less, which is expressed by a ratio (Wp/We) of plastic deformation energy Wp to elastic deformation energy We; and a ratio (Tmf/Tm) of the thickness Tmf of the metal-free, hard carbon layer to the thickness Tm of the metal-containing, hard carbon layer being 2-8.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: May 9, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Akira Kunimoto, Masaki Moronuki
  • Combined oil control ring
    Patent number: 9618115
    Abstract: A combined oil control ring comprising a pair of circular side rails each having a gap, and a waved spacer expander longitudinally sandwiched by the side rails, which has seating tabs for pushing inner surfaces of the side rails on the inner side, (a) the radial thickness a1 of the side rail being 50-90% of the height a9 of the spacer expander, or (b) the height a10 of the seating tab being 23-60% of the height a9 of the spacer expander.
    Type: Grant
    Filed: April 17, 2014
    Date of Patent: April 11, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Hiroyuki Yabune, Masaaki Fujita, Hiroyuki Sugihara
  • Compression ring and its production method
    Patent number: 9617952
    Abstract: To provide a price-competitive compression ring having excellent thermal conductivity and thermal sag resistance, which can be used in a high-thermal-load environment of high-compression-ratio engines, steel identified by the material number of SUP10 in JIS G 4801, which contains small amounts of alloying elements, is used, and a piston ring wire is annealed before an oil-tempering treatment such that spheroidal cementite having an average particle size of 0.1-1.5 ?m is dispersed in a tempered martensite matrix, thereby suppressing the movement of dislocation and creep even at 300° C., and improving thermal sag resistance.
    Type: Grant
    Filed: May 24, 2011
    Date of Patent: April 11, 2017
    Assignees: KABUSHIKI KAISHA RIKEN, TOKUSEN KOGYO CO., LTD.
    Inventors: Yuji Shima, Junya Takahashi, Ryouichi Kamon
  • VALVE SEAT OF SINTERED IRON-BASED ALLOY
    Publication number: 20170089228
    Abstract: The present invention provides a valve seat of a Co-free, sintered iron-based alloy having excellent heat resistance, oxidation resistance and wear resistance, as well as excellent machinability, which is usable for internal combustion engines using a gas fuel. The valve seat is produced by using a prealloy containing 12% or more by mass of Cr in a matrix for, and hard particles having high strength and hardness at high temperatures are used, such that the entire valve seat has a composition comprising by mass 5.0-20.0% of Cr, 0.4-2.0% of Si, 2.0-6.0% of Ni, 5.0-25.0% of Mo, 0.1-5.0% of W, 0.5-5.0% of V, 1.0% or less of Nb, and 0.5-1.5% of C, the balance being Fe and inevitable impurities.
    Type: Application
    Filed: February 10, 2015
    Publication date: March 30, 2017
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Akiko SHIMADA, Hiroji HENMI
  • Compression ring and its production method
    Patent number: 9599223
    Abstract: To provide a price-competitive compression ring having excellent thermal conductivity and thermal sag resistance, which can be used in a high-thermal-load environment of high-compression-ratio engines, steel identified by the material number of SKS93 in JIS G 4404 is used, and a piston ring wire is annealed before an oil-tempering treatment such that spheroidal cementite having an average particle size of 0.1-1.5 ?m is dispersed in a tempered martensite matrix.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: March 21, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Yuji Shima, Ryouichi Kamon
  • Member having hydrogen-containing, hard, amorphous carbon coating and its production method
    Patent number: 9546425
    Abstract: In a member having a hydrogen-containing, amorphous carbon coating having a relatively smooth surface, similarly amorphous, fine carbon particles are dispersed in the hydrogen-containing, amorphous carbon coating to have improved cracking resistance while keeping smoothness on the surface and hardness in the entire coating. Specifically, fine particles discharged from a carbon cathode of an arc evaporation source by arc discharge are introduced into the coating, so that similarly amorphous, fine carbon particles are dispersed in the hydrogen-containing, amorphous carbon coating.
    Type: Grant
    Filed: January 17, 2011
    Date of Patent: January 17, 2017
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventor: Katsuhiro Tsuji
  • PISTON RING AND ITS PRODUCTION METHOD
    Publication number: 20170009314
    Abstract: To provide a piston ring of low-alloy steel having excellent nitridability, namely, a piston ring of low-alloy steel having excellent thermal conductivity and capable of being provided with a sufficient nitrided layer, steel comprising by mass 0.45-0.65% of C, 0.15-0.35% of Si, 0.65-1.00% of Mn and 0.60-1.10% of Cr as indispensable alloy elements, and less than 0.35% of Mo, less than 0.25% of V and less than 0.001% of B as optional alloy elements, the total amount of the indispensable alloy elements and the optional alloy elements being less than 3.0% by mass, is formed into a piston ring; and the nitrided layer is formed on its surface.
    Type: Application
    Filed: January 22, 2015
    Publication date: January 12, 2017
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventor: Yuji SHIMA
  • Seal ring
    Patent number: 9506564
    Abstract: A plurality of concave portion to be spaced apart from each other in a circumferential direction through a pillar portion is formed in an inner circumferential side of a side surface of a seal ring mounted in a shaft groove formed in an outer circumferential surface of a shaft. The concave portion including a deepest portion, and two inclined portions, connects the inclined portion positioned at an opposite side in a rotational direction and the adjacent pillar portion with a curved surface having a shape convex, and further, makes a width in the circumferential direction of the inclined portion of the rotational direction side smaller than a width in the circumferential direction of the inclined portion of the opposite side in the rotational direction.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: November 29, 2016
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Junya Nagai, Mika Saito, Tomoya Shibano
  • PISTON RING
    Publication number: 20160305545
    Abstract: A disclosed piston ring comprises an annular body, and a joint formed in the body, wherein, in the joint, a first protruding part that protrudes from one butt end toward the other butt end and a first reception part that receives the first protruding part in the other butt end are provided, a second protruding part that protrudes from the other butt end toward the one butt end and a second reception part that receives the second protruding part in the one butt end are provided, a first male part that protrudes from the second protruding part and a first female part that receives the first male part in the second reception part are provided, and a second male part that protrudes from the second reception part and a second female part that receives the second male part in the second protruding part are provided.
    Type: Application
    Filed: December 26, 2014
    Publication date: October 20, 2016
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Fumihiro OKAZAKI, Masaaki FUJITA
  • Piston ring
    Patent number: 9447879
    Abstract: To provide a piston ring having a hard laminate coating for excellent scuffing resistance, wear resistance and peeling resistance, which can be used in an environment of high mechanical and thermal load in engines, the piston ring is provided with a hard laminate coating as thick as 10-60 ?m on its outer peripheral surface, the laminate coating being formed by alternately laminating two types or more of layers made of different compounds, each of the compound layers being made of nitride of at least one metal selected from the group consisting of Ti, Cr, Zr, V, Hf and Al.
    Type: Grant
    Filed: December 6, 2013
    Date of Patent: September 20, 2016
    Assignee: KABUSHIKI KAISHA RIKEN
    Inventors: Masayuki Sato, Yuuichi Murayama, Youhei Iwamoto
  • PISTON RING FOR INTERNAL COMBUSTION ENGINE
    Publication number: 20160265660
    Abstract: Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ring 1 for the internal combustion engine including a piston ring body 11 having at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film 12, wherein the aluminum cohesion resistance film 12 has a first coating film 12a made of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film 12a.
    Type: Application
    Filed: October 16, 2014
    Publication date: September 15, 2016
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Hayato SASAKI, Takashi ONO, Yongtie YAN
  • PISTON RING AND ITS PRODUCTION METHOD
    Publication number: 20160238133
    Abstract: To provide a hard-amorphous-carbon-coated piston ring having low friction and excellent wear resistance and peeling resistance to reduce the fuel consumption of automobiles, an outer peripheral surface of a steel-made piston ring base material is provided with a primary layer constituted by a CrN/Cr laminate coating or a CrN/TiN laminate coating as thick as 10-60 ?m, which is obtained by alternately laminating CrN-type chromium nitride and chromium metal or TiN-type titanium nitride, an intermediate layer of chromium metal and/or titanium metal as thick as 0.05-1.0 ?m, and then a hard amorphous carbon coating as thick as 0.4-20 ?m.
    Type: Application
    Filed: October 27, 2014
    Publication date: August 18, 2016
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Masayuki SATO, Yuuichi MURAYAMA, Youhei IWAMOTO, Takuma SEKIYA
  • PISTON RING
    Publication number: 20160238132
    Abstract: To provide a piston ring having a hard laminate coating having excellent scuffing resistance, wear resistance and peeling resistance, which can be used in an environment of high mechanical and thermal load in engines, the piston ring is provided on its outer peripheral sliding surface with a CrN-type hard coating as thick as 10-60 ?m and comprising a CrN/CrCN laminate coating having hardness Hv of 1000 or more and residual compression stress of 1500 MPa or less, a laminate unit composed of a CrN layer and a CrCN layer being as thick as 30 nm or more; the CrN/CrCN laminate coating being formed by alternately laminating CrN layers and CrCN layers containing C dissolved in CrN by ion plating.
    Type: Application
    Filed: September 26, 2014
    Publication date: August 18, 2016
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Masayuki SATO, Yuuichi MURAYAMA, Youhei IWAMOTO, Takuma SEKIYA
  • Seal Ring
    Publication number: 20160238134
    Abstract: A seal ring includes a center axis, an outer peripheral surface, an inner peripheral surface, a side surface, and a groove. The center axis is a rotation center. The outer peripheral surface is an outward cylindrical surface whose center is positioned at the central axis. The inner peripheral surface is an inward cylindrical surface disposed between the center axis and the outer peripheral surface whose center is positioned at the central axis. The side surface connects the outer peripheral surface and the inner peripheral surface. The groove is formed in a dented groove from the side surface, extends along a radial direction spaced from the outer peripheral surface, has a first end connected to the inner peripheral surface and a second end at an opposite side of the first end, and returns oil entered from the first end to an inner peripheral surface side via the second end.
    Type: Application
    Filed: September 17, 2014
    Publication date: August 18, 2016
    Applicant: Kabushiki Kaisha Riken
    Inventors: Naohisa OHYA, Junya NAGAI
  • COMBINATION OF CYLINDER BORE AND PISTON RING
    Publication number: 20160230697
    Abstract: To provide a combination of a cylinder bore and a piston ring having excellent scuffing resistance and wear resistance with low friction loss even under severe sliding conditions with a high load applied to an engine, by a thermal spraying technique of a cylinder bore enabling the use of a usual die-cast aluminum alloy, a thermally sprayed iron-based coating formed on a piston-ring-sliding surface of a cylinder bore, which has Rpk of less than 0.20 ?m in a surface roughness profile, is combined with a hard carbon coating formed on an outer peripheral sliding surface of the piston ring, which has Rpk of less than 0.15 ?m in a surface roughness profile, in an internal combustion engine.
    Type: Application
    Filed: September 16, 2014
    Publication date: August 11, 2016
    Applicant: KABUSHIKI KAISHA RIKEN
    Inventors: Akio SHINOHARA, Masaki MORONUKI