Patents by Inventor Iwao Imai

Iwao Imai 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: 4516319
    Abstract: To reduce the breakdown potential magnitude between the output tip surface of an ignition distributor rotor output segment and each of the output terminals of the distributor cap, the rotor output segment is made of a low thermally conductive material 0.1 mm to 1.00 mm thick, and a layer of a silicone dielectric material such as a silicone plate, viz., a plate including at least a sheet of silicone varnish-containing glass cloth, is secured to at least a portion of at least one of the top and bottom surface areas of the rotor output segment.
    Type: Grant
    Filed: October 17, 1983
    Date of Patent: May 14, 1985
    Assignees: Nissan Motor Co., Ltd., Hitachi, Ltd.
    Inventors: Masazumi Sone, Iwao Imai, Hiromitsu Nagae
  • Patent number: 4510915
    Abstract: An N cylinder internal combustion engine plasma ignition system comprises a DC-DC converter for boosting low DC voltage to high DC voltage. Each of N ignition energy charging circuits includes a first capacitor connected between the DC-DC converter and ground via first and second diodes. The capacitor is charged by the DC-DC converter. Each of N reverse blocked thyristors connected to a junction of the first diode and first capacitor selectively grounds an electrode of the corresponding first capacitor to discharge ignition energy stored in the first capacitor. For each cylinder a transformer connected between the first capacitor and a spark plug boosts and feeds the discharged energy to the plug. One end of the transformer primary winding is grounded via a second capacitor to generate a damped oscillation when the corresponding thyristor grounds the first capacitor.
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: April 16, 1985
    Assignee: Nissan Motor Company, Limited
    Inventors: Yasuki Ishikawa, Hiroshi Endo, Masazumi Sone, Iwao Imai
  • Patent number: 4495421
    Abstract: An optical power supply switching apparatus by which a battery power can be connected to or disconnected from at least one electric appliance provided for an automotive vehicle without generating electromagnetic noise or electromagnetic interference between the electric appliance and other audio equipment. The optical power supply switching apparatus according to the present invention comprises at least one light-emitting element, one optical fiber, at least one photoelectric transducer, at least one semiconductor contactless switching element, and a plurality of optical directional-couplers and optical filters where necessary, in addition to a special low-impedance coaxial power distribution line.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: January 22, 1985
    Assignee: Nissan Motor Company, Limited
    Inventors: Hiroshi Endo, Masazumi Sone, Iwao Imai, Hideo Kasuya
  • Patent number: 4473755
    Abstract: A device for preventing noise leakage externally from a digital electronic apparatus using a clock pulse generator, comprising: (a) a metal casing; (b) a printed circuit board housed within the metal casing into which the digital electronic apparatus is assembled having a plurality of land patterns formed thereon at the end of various signal lines of the digital electronic apparatus; (c) a connector attached at one end of the printed circuit board having a plurality of connector pins therewithin for connecting said land patterns with external various apparatus; (d) an insulative film positioned on one surface of the printed circuit board closely adjacent to the land patterns; (e) a conductive film coated on one surface of the insulative member and coupled electrically to the metal casing; and (f) a plurality of chip-type capacitors which bridges between the conductive film and plurality of land patterns for effecting noise filtering and a method of manufacturing the device described above comprising the steps
    Type: Grant
    Filed: April 8, 1982
    Date of Patent: September 25, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Iwao Imai, Hiroshi Endo, Masazumi Sone, Hideo Kasuya
  • Patent number: 4455989
    Abstract: A plasma ignition system for an internal combustion engine which varies a discharge time of a plasma ignition energy charged capacitor according to the engine operating condition, e.g., the current engine speed.
    Type: Grant
    Filed: June 15, 1982
    Date of Patent: June 26, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Hiroshi Endo, Masazumi Sone, Iwao Imai, Yasuki Ishikawa
  • Patent number: 4448181
    Abstract: A plasma ignition system for an engine having any number of engine cylinders, which comprises: (A) a plurality of plasma ignition plugs each mounted within a corresponding engine cylinder; (B) a first power supply unit for supplying a first electric power into each plasma ignition plug so as to generate a spark discharge within each plasma ignition plug; (C) a first switching circuit for sequentially connecting the first power supply unit to each plasma ignition plug according to a predetermined ignition order; (D) a second power supply unit for supplying a second electric power into each plasma ignition plug so as to generate a high-temperature plasma gas within each plasma ignition plug; and (E) a second switching circuit for sequentially connecting two of the plasma ignition plugs within the respective engine cylinders, one engine cylinder being at the start of an explosion stroke and the other engine cylinder being at almost end of an exhaust stroke, in a predetermined delay after the occurrence of the sp
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: May 15, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Yasuki Ishikawa, Hiroshi Endo, Masazumi Sone, Iwao Imai
  • Patent number: 4445491
    Abstract: In an auxiliary ignition system for starting a diesel engine having a plurality of plasma spark plugs installed in corresponding combustion chambers facing fuel injection valves, starting time is reduced by applying high ignition energy to the plugs following predetermined time intervals after fuel injection to the corresponding engine cylinders.
    Type: Grant
    Filed: August 16, 1982
    Date of Patent: May 1, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Yasuki Ishikawa, Hiroshi Endo, Masazumi Sone, Iwao Imai
  • Patent number: 4441479
    Abstract: An ignition system for a multi-cylinder internal combustion engine having a spark plug within each engine cylinder, wherein a single DC-DC converter is provided and a high-voltage withstanding characteristic capacitor is provided for each spark plug. The capacitor charges to the high DC output voltage of the DC-DC converter and operatively supplies the high DC voltage via a boosting transformer into the corresponding spark plug at a predetermined ignition timing. The amount of the discharge energy being varied according to the pulse width of an input signal of each switching circuit which operates to supply the charged high DC voltage of the capacitor into the corresponding spark plug, the pulse width being varied according to various engine operating conditions.
    Type: Grant
    Filed: July 30, 1982
    Date of Patent: April 10, 1984
    Assignee: Nissan Motor Company, Limited
    Inventors: Hiroshi Endo, Masazumi Sone, Iwao Imai, Yasuki Ishikawa
  • 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: 4425485
    Abstract: To reduce the breakdown potential magnitude between the output tip surface of an ignition distributor rotor output segment and each of the output terminals of the distributor cap, the rotor output segment is made of a low thermally conductive material 0.1 mm to 1.00 mm thick, and a layer of a silicone dielectric material such as a silicone plate, viz., a plate including at least a sheet of silicone varnish-containing glass cloth, is secured to at least a portion of at least one of the top and bottom surface areas of the rotor output segment.
    Type: Grant
    Filed: July 24, 1981
    Date of Patent: January 10, 1984
    Assignees: Nissan Motor Co., Ltd., Hitachi, Ltd.
    Inventors: Masazumi Sone, Iwao Imai, Hiromitsu Nagae
  • Patent number: 4419547
    Abstract: An ignition distributor wherein either a rotor electrode or each of cap electrodes is made of semiconductive alumina ceramics. The semiconductive alumina ceramics contains from 10% to 40% by weight titania (TiO.sub.2).
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: December 6, 1983
    Assignees: Nissan Motor Company, Ltd., Hitachi, Ltd.
    Inventors: Iwao Imai, Masazumi Sone
  • 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: 4403350
    Abstract: An electronic system for controlling engine parameters or the like such as the amount of fuel supplied to the internal combustion engine of an automotive vehicle having a radio receiver, the control system having a plurality of digital processing units such as microcomputers, where each unit operates in synchronization with a clock pulse. There is provided a clock pulse generator for each digital processing unit, the frequency of which is selected so that the higher harmonics of one clock pulse has a frequency difference of 10 KHz or more from the higher harmonics of other clock pulses in a broadcast band, whereby interference which can disturb the reception of a broadcast signal is avoided.
    Type: Grant
    Filed: April 20, 1981
    Date of Patent: September 6, 1983
    Assignee: Nissan Motor Company Limited
    Inventors: Iwao Imai, Masazumi Sone
  • Patent number: 4396855
    Abstract: A plasma jet ignition plug comprises an electric insulator formed with a discharge cavity and a plurality of electrodes communicating with the discharge cavity to form, within the discharge cavity, a spark gap. The plurality of electrodes include a central electrode connected to a high voltage electric source and a low voltage electric source, and a peripheral electrode which is grounded. The peripheral electrode substantially closes the discharge cavity and is formed with a jet opening. At least that part of at least one of the plurality of electrodes which communicates with the discharge cavity is made of a material selected from a group consisting of ferrite, a nickel alloy containing at least one of silicon, aluminum and magnesium, and electrically conductive ceramic.
    Type: Grant
    Filed: June 12, 1980
    Date of Patent: August 2, 1983
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Iwao Imai, Masazumi Sone
  • Patent number: 4369343
    Abstract: An apparatus for suppressing noise radiating from an ignition system for an internal combustion engine is disclosed. The ignition system comprises a distributor which uses an electrically conductive ceramic or a PTC (Positive Temperature Coefficient) thermistor as a material for a rotary electrode and/or stationary electrodes. At least a spark discharging portion of the rotary electrode and/or spark discharging portions of the stationary electrodes are formed from the electrically conductive ceramic which has a resistivity ranging from 10.sup.-6 to 10.sup.-2 ohm.multidot.cm or from the PTC thermistor. Cooperating with them are the high resistor spark plug and the high tension resistor cable. The high resistor spark plug herein disclosed uses an elongate monolithic resistor which has a length not shorter than 8 mm and preferrably has a length of 15 mm.
    Type: Grant
    Filed: November 21, 1980
    Date of Patent: January 18, 1983
    Assignees: Nissan Motor Co., Ltd., Hitachi, Ltd.
    Inventors: Masazumi Sone, Iwao Imai
  • 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
  • Patent number: 4327702
    Abstract: A plasma jet ignition system wherein a plasma jet energy storage system is used in conjunction with a spark energy storage system to provide energy to a plasma jet ignition plug. For the purpose of suppressing noise due to the spark discharge, a spark energy delivery cable takes the form of a high tension resistance cable and a plasma jet energy delivery cable takes the form of a lead including a coil and having a distributed inductance.
    Type: Grant
    Filed: April 18, 1980
    Date of Patent: May 4, 1982
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Iwao Imai, Masazumi Sone
  • Patent number: 4308488
    Abstract: A plasma jet ignition system wherein a plasma jet energy storage system is designed as an add-on system, which is used in conjunction with a conventional ignition system which provides the basic spark timing and high voltage trigger signal to plasma jet ignition plugs. The plasma jet energy storage system is connected to the plasma jet ignition plugs via steering diodes. Each of the steering diodes has an anode terminal directly connected to one of the plasma jet ignition plugs.
    Type: Grant
    Filed: April 18, 1980
    Date of Patent: December 29, 1981
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Iwao Imai, Yukitsugu Hirota