Patents by Inventor Toshikazu Kurokawa

Toshikazu Kurokawa 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: 5123382
    Abstract: An intake system for an engine allows supercharging using the dynamic effect of intake air has a surge tank for a cylinder group in which cylinders are ignited in a sequence discontinuous with each other, a second surge tank for another cylinder group in which cylinders are ignited in a sequence discontinuous with each other, a first upstream intake passage for supplying intake air to the first surge tank, a second upstream intake passage for supplying intake air to the second surge tank, a connecting tank for communicating intermediate portions of the individual intake passages with each other, and a short connecting passage for communicating upstream portions of the first upstream intake passage and the second upstream intake passage with the connecting tank 9.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: June 23, 1992
    Assignee: Mazda Motor Corporation
    Inventors: Motoi Aoki, Toshikazu Kurokawa, Fusatosi Tanaka, Kouji Matsuura
  • Patent number: 5121733
    Abstract: An air intake system for a supercharged automotive engine has an independent air intake passage an end of which is communicated independently and separately with a combustion chamber of each cylinder and a supercharger for supercharging intake air. The air intake valve closing timing is delayed after bottom dead point and the independent air intake passage is shaped so that the number of revolutions which causes maximum inertia in the independent air intake passage by supercharging in a high-speed region is higher than the number of revolutions of the engine at which maximum horse power is generated.
    Type: Grant
    Filed: October 24, 1990
    Date of Patent: June 16, 1992
    Assignee: Mazda Motor Corporation
    Inventors: Tsuyoshi Goto, Kouichi Hatamura, Toshikazu Kurokawa
  • Patent number: 5109811
    Abstract: Each surge tank disposed over the respective cylinder head of the combustion engine is connected to the intake port of each cylinder of the combustion engine individually and independently through the independent intake passages. The independent intake passages form a space, i.e. a dead space, in association with the surge tank and the cylinder head, and a first volume chamber or a second volume chamber is disposed within the space in order to provide the dynamic effect of intake air. The dynamic effect of intake air is achieved at least either of resonance supercharging or inertia supercharging.
    Type: Grant
    Filed: May 9, 1991
    Date of Patent: May 5, 1992
    Assignee: Mazda Motor Corporation
    Inventors: Fusatoshi Tanaka, Toshikazu Kurokawa, Kouji Matsuura, Motoi Aoki
  • Patent number: 5081962
    Abstract: A fuel intake system for a combustion engine of a type having V-shaped first and second cylinder banks and also having a crank axis of the crankshaft, which comprises a throttle casing disposed in a center space delimited between the first and second cylinder banks, elongated first and second surge tanks extending in a direction parallel to the crank axis and disposed on respective sides of the center space, and a passage system communicating the throttle casing to each of the first and second surge tanks. The passage system comprises a merging region communicated with the throttle casing and first and second branch ducts branched off from one end of the merging region opposite to the throttle casing. The first and second branch ducts connect to the first and second surge tanks, respectively. Each of the first and second branch ducts is comprised of two independent passages spaced apart from each other in a direction parallel to the crank axis.
    Type: Grant
    Filed: March 29, 1991
    Date of Patent: January 21, 1992
    Assignee: Mazda Motor Corporation
    Inventors: Toshikazu Kurokawa, Fusatoshi Tanaka, Kouji Matsuura, Motoi Aoki
  • Patent number: 5056472
    Abstract: A four cycle, 12-cylinder engine includes four cylinder groups each having three cylinders located adjacent to each other. The cylinders in each cylinder group have intake strokes which are apart one from another by 240.degree. in terms of angle of rotation of the engine crankshaft. The cylinders in each cylinder group are connected through respective branch intake passages with a common intake passage. Means is provided for separating the common intake passage of one cylinder group from the common intake passage of another cylinder group.
    Type: Grant
    Filed: June 4, 1990
    Date of Patent: October 15, 1991
    Assignee: Mazda Motor Corporation
    Inventors: Toshikazu Kurokawa, Hiroshi Sumimoto, Takashiga Tokushima, Tadao Suemori
  • Patent number: 5022354
    Abstract: A cooling system for a V-type engine includes a radiator, having inlet and outlet conduits extending between the radiator and the engine, which cools coolant introduced therein through the inlet conduit, and a water pump with an inlet port, disposed between the engine body and the radiator, which circulates the coolant, leaving the radiator through the outlet conduit, through the engine body. Between the radiator and water pump, the cooling system is provided with a bypass passage, which communicates a passage, connecting both of the outlet ports to the inlet conduit, with a downstream part of the outlet conduit where a thermostat is installed, and a suction passage which communicates the inlet port of the water pump with the downstream part of the outlet conduit by a suction passage.
    Type: Grant
    Filed: September 11, 1990
    Date of Patent: June 11, 1991
    Assignee: Mazda Motor Corporation
    Inventors: Junichi Okita, Toshikazu Kurokawa
  • Patent number: 4932368
    Abstract: In a V-type internal combustion engine having a pair of upwardly diverging cylinder banks and an auxiliary unit disposed at an upper portion in a space defined between the cylinder banks, a suction arrangement includes intake ports provided at an inner side of the respective cylinder banks, inclined inwardly by a predetermined angle with respect to respective clyinder axes, and extending upwardly in a generally vertical direction so as not to interfere with the auxiliary unit, and cylinder communicating portions connected to upper portions of the intake ports in communication with the respective cylinders to permit the introduction of the intake gas thereto.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: June 12, 1990
    Assignee: Mazda Motor Corporation
    Inventors: Ryoji Abe, Setsuo Harada, Kouji Asanomi, Kouichi Hatamura, Toshikazu Kurokawa, Tsuyoshi Goto, Shinji Seike