Patents by Inventor Yasuki Ishikawa

Yasuki Ishikawa 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: 4433669
    Abstract: A plasma ignition system for an internal combustion engine having a plasma ignition plug within each of the engine cylinders, which comprises: (a) a low DC voltage supply such as a vehicle battery; (b) a high surge voltage generator which generates and distributes a high surge voltage having a negative peak value of about minus 15 kilovolts into one of the plasma ignition plugs according to a predetermined ignition order so as to generate a spark discharge at the plasma ignition plug; (c) a DC-DC converter which boosts the low DC voltage sent from the low DC voltage supply to a high DC voltage; (d) a plurality of plasma ignition energy charging means each of which charges the high DC voltage supplied from the DC-DC converter; (e) a plurality of thyristors each for connecting the plasma ignition energy charging means to the corresponding plasma ignition energy charging means to the corresponding plasma ignition plug in response to a first trigger signal applied thereat; (f) a trigger signal generator which gen
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: February 28, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Yasuki Ishikawa, Hiroshi Endo, Masazumi Sone, Iwao Imai
  • Patent number: 4418660
    Abstract: A plasma ignition system for an internal combustion engine, which comprises: (a) a low DC voltage power supply; (b) a DC-DC converter which converts a low DC voltage from the low DC voltage supply to the corresponding AC voltage and inverts the AC voltage to a high DC voltage; (c) a plurality of plasma ignition plugs each located within one of the cylinders; (d) a plurality of first capacitors each for changing the high DC voltage received from the DC-DC converter; (e) a plurality of photosensitive switching elements each connected between each corresponding first capacitor and ground and which turns on to apply the plasma ignition energy charged within the corresponding first capacitor to the corresponding plasma ignition plug at a predetermined timing; (f) a plurality of voltage-boosting transformers each having a common terminal of primary and secondary windings connected to one terminal of each corresponding plasma ignition energy capacitor and another terminal of the primary winding connected to the corr
    Type: Grant
    Filed: April 7, 1982
    Date of Patent: December 6, 1983
    Assignee: Nissan Motor Company, Limited
    Inventors: Hiroshi Endo, Masazumi Sone, Iwao Imai, Yasuki Ishikawa
  • Patent number: 4366801
    Abstract: A plasma ignition system for an internal combustion engine which can prevent irregular ignition when the insulation between the electrodes of the spark plug deteriorates due to carbon on the electrodes, and further can prevent electrical noise from being emitted. The system according to the present invention comprises a plurality of independent plasma ignition energy storing condensers, switching units, and boosting transformers one each for each of the engine cylinder. In this system, a high tension is generated at the secondary coil of the boosting transformer to generate a spark between the electrodes of the plug and subsequently a large current is passed through the electrodes by the remaining energy stored in the condenser.
    Type: Grant
    Filed: September 17, 1981
    Date of Patent: January 4, 1983
    Assignee: Nissan Motor Company, Limited
    Inventors: Hiroshi Endo, Yasuki Ishikawa, Iwao Imai