Patents by Inventor Kentaro Takahashi

Kentaro Takahashi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4583502
    Abstract: A wear-resistant member and method for producing the same which member may form a movable member in an internal combustion engine which is subjected to high pressure such as a rocker arm, tappet, cam, valve or valve seat. The member is formed as a combination of a ferrous sintered body and a ferrous base body having a common surface. The sintered body is formed from a compressed powder body disposed in contact with the ferrous base body. The powder body, in a preferred embodiment, consists of 0.5 to 7.0% by weight carbon, 0.1 to 5.0% phosphorus, the balance being iron, and having a porosity of 12 to 20% by volume at least 40% of which is pores having a pore size of not more than 300 .mu.. The combined powder body and ferrous base body are heated to a temperature higher than the liquid-phase temperature of the powder body but lower than the melting point of the ferrous body to sinter the powder body.
    Type: Grant
    Filed: February 20, 1980
    Date of Patent: April 22, 1986
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Takeshi Hiraoka, Yoshikatsu Nakamura, Masajiro Takeshita
  • Patent number: 4582271
    Abstract: A continuous delivery apparatus for continuously feeding a lengthy work material wound into an approximately ring-like form to a press or the like. This apparatus comprises a rotatable turn-table on which wound material is placed so that an axis of the material is crossed perpendicular to the turn-table, a motor for rotating and driving the turn-table, and a swing arm, one end of which is supported on a rotating shaft whereas the other end thereof is pivotable from a center of the wound work material to an outer peripheral direction, said swing arm being always biased in an outer peripheral direction. The swing arm which is pivotally moved with a change in wound amount of work material is removed as an amount of rotation of the rotating shaft, said amount of rotation controlling the rotational speed of a motor to deliver work material at a constant speed at all times.
    Type: Grant
    Filed: July 28, 1983
    Date of Patent: April 15, 1986
    Inventor: Kentaro Takahashi
  • Patent number: 4363662
    Abstract: An abrasion resistant ferro-based sintered alloy comprising 1.1 to 1.6% by weight of carbon, 1.5 to 3.5% by weight of chromium, 1.6 to 2.9% by weight of molybdenum, 1.0 to 3.0% by weight of nickel, 3.0 to 5.0% by weight of cobalt, 0.5 to 1.5% by weight of tungsten, 1.8 to 18.0% by weight of copper and the balance iron wherein said alloy contains particles of specific alloy comprising C-Cr-W-Co and ferromolybdenum particles are uniformly dispersed in the base structure comprising a mixture of pearlite, bainite and martensite and wherein nickel and cobalt are distributed around the particles of specific alloy and of ferromolybdenum alloy is disclosed.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: December 14, 1982
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Takeshi Hiraoka, Shigeru Urano
  • Patent number: 4360383
    Abstract: An abrasion resistant sintered alloy for use in internal combustion engines which comprises 0.5 to 4.0% by weight of carbon, 5.0 to 30.0% by weight of Cr, 1.5 to 16.0% by weight of Nb, 0.1 to 4.0% by weight of Mo, 0.1 to 10.0% by weight of Ni and 0.1 to 5.0% by weight of P, which permits liquid-phase sintering at temperatures not higher than 1,250.degree. C., and have 0.2 to 10% by volume of sintering pores at least 40% of which consist of pores having a pore size of not larger than 150 .mu.m, is disclosed.
    Type: Grant
    Filed: April 28, 1980
    Date of Patent: November 23, 1982
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Yoshikatsu Nakamura, Masajiro Takeshita
  • Patent number: 4345942
    Abstract: An abrasion resistered sintered alloy for use in internal combustion engines which comprises 0.5 to 4.0% by weight of carbon, 1.5 to 16.0% by weight of Nb, 0.1 to 4.0% by weight of Mo, 0.1 to 1.0% by weight of Ni and 0.1 to 5.0% by weight of P which permits liquid-phase sintering at temperatures not higher than 1,250.degree. C., and have 0.2 to 10% by volume of sintering pores at least 40% of which consist of pores having a pore size of not larger than 150 .mu.m is disclosed.
    Type: Grant
    Filed: April 24, 1980
    Date of Patent: August 24, 1982
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Yoshikatsu Nakamura, Masajiro Takeshita
  • Patent number: 4345943
    Abstract: An abrasion resistant sintered alloy for use in internal combustion engines which comprises 0.5 to 4.0% by weight of C, 5.0 to 3.0% by weight of Cr, less than 10.0% by weight of at least one of Ni, Mo, Co and Cu, 0.1 to 5.0% by weight of at least one of P, B and Si which permits liquid-phase sintering at temperatures not higher than 1,250.degree. C. and the balance iron, and have hardness after sintering of Hv 500 to 1,200, 7 to 45% by area ratio of cementite or eutectic crystal of cementite and P and 0.2 to 10% by volume of sintering pores at least 40% of which consist of pores having a pore size of not larger than 150 .mu.m.
    Type: Grant
    Filed: April 24, 1980
    Date of Patent: August 24, 1982
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Yoshikatsu Nakamura, Masajiro Takeshita
  • Patent number: 4243414
    Abstract: A slidable member for a prime mover made of an abrasion resistant liquid-phase sintered alloy, containing 0.5 to 4.0% by weight of carbon, 8.0 to 30.0% by weight of chromium, and 0.1 to 5.0% by weight of at least one of phosphorus, boron and silicon which permit liquid-phase sintering at not more than 1,250.degree. C., and the balance iron. The sintered alloy has 0.2 to 10% by volume of sintering pores at least 40% of which consist of pores having a pore size of not more than 150.mu..
    Type: Grant
    Filed: October 27, 1978
    Date of Patent: January 6, 1981
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Yoshikatsu Nakamura, Masajiro Takeshita
  • Patent number: 4123265
    Abstract: A method of producing a ferrous alloy material having improved wear resistance comprising (1) mixing powders of a ferrous alloy, tungsten and optionally at least one element selected from the group consisting of C, Ni, Mn, Mo, Cr, and Cu, (2) sintering the mixture of powders of step (1) to form a sintered product, (3) infiltrating the sintered product of step (2) with molten copper or a copper alloy to produce an infiltrated sintered product and (4) cooling the infiltrated sintered product of step (3).
    Type: Grant
    Filed: February 23, 1977
    Date of Patent: October 31, 1978
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Shigeru Urano
  • Patent number: 4088476
    Abstract: An abrasion-resistant cast iron having extremely good resistances to scuffing and abrasion, comprising a pearlite matrix and 2 to 15% of boron carbide and 2 to 7% of graphite flakes, the percentages being in terms of percent areas. The cast iron is useful, for example, for piston rings and cylinder liners of internal combustion engines.
    Type: Grant
    Filed: October 29, 1976
    Date of Patent: May 9, 1978
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Tsutomu Takao, Kentaro Takahashi
  • Patent number: 4079720
    Abstract: Improved wear characteristics of a seal ring for a piston and a mating cylinder are obtained by using selected materials for the seal ring and cylinder. The cylinder is characterized by having a surface coating of Ni or Ni alloy containing 3% to 8% of SiC having a particle size of from 0.5.mu. to 5.mu., or by having a base member of Al or Al alloy containing 13% to 23% of Si having a particle size of 5.mu. to 8.mu.. The seal ring is characterized by having a Ni or Ni alloy containing 2% to 10% of SiC having a particle size of 0.5.mu. to 5.mu..
    Type: Grant
    Filed: May 11, 1976
    Date of Patent: March 21, 1978
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventor: Kentaro Takahashi
  • Patent number: 3988119
    Abstract: An abrasion and scuff resistant piston ring having an outer peripheral surface formed by the simultaneous spray deposition of from 30 to 95% of molten molybdenum and from 5 to 70% of molten iron alloy.
    Type: Grant
    Filed: January 2, 1975
    Date of Patent: October 26, 1976
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Kentaro Takahashi, Yoshikatsu Nakamura