Patents by Inventor Yoshifumi Murakami

Yoshifumi Murakami 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: 7027911
    Abstract: A control apparatus for an engine increases an intake air quantity just before engine stop to increase a compression pressure in a compression stroke. As the compression pressure is increased, a negative torque in the compression stroke increases and obstructs engine rotation, and brakes the engine rotation. Thus, a range of crank angle, in which torque is below engine friction, that is, in which engine rotation can be stopped, is reduced. As a result, variation in engine rotation stop position is reduced to be within a small range of crank angle. Information of engine rotation stop position is stored, and the stored information of engine rotation stop position is used at the start of an engine to accurately determine an initial injection cylinder and an initial ignition cylinder to start the engine.
    Type: Grant
    Filed: January 22, 2004
    Date of Patent: April 11, 2006
    Assignee: Denso Corporation
    Inventors: Seiichirou Nishikawa, Yoshifumi Murakami
  • Publication number: 20060053894
    Abstract: A pressure sensor includes a hollow cylindrical stem, a sensor chip, and a wiring board. The hollow cylindrical stem has a pressure-sensitive flexible diaphragm at a first axial end thereof and an opening at a second axial end thereof, the opening for transmitting pressure into the stem. The sensor chip is provided on the diaphragm for outputting an electrical signal in proportion to the deformation of the diaphragm. The wiring board electrically connects the sensor chip to an external circuit. The wiring board is located around the sensor chip on the first axial end of the stem.
    Type: Application
    Filed: September 8, 2005
    Publication date: March 16, 2006
    Inventors: Tomohito Kunda, Osamu Ito, Yoshifumi Murakami, Takeshi Shinoda
  • Publication number: 20060016413
    Abstract: During a shut-down period of an engine based on an idle stop control, a computer estimates a power stroke cylinder and a compression stroke cylinder when the engine is stopped. A fuel is injected into the power stroke cylinder and the compression stroke cylinder in an intake stroke just before the engine is stopped. An air-fuel mixture is hold in each cylinder with the engine stopped. When an auto start is required while the engine is stopped, a spark ignition is performed in the power stroke cylinder to start cranking of the engine by combustion energy. At nest ignition timing, a spark ignition is performed in the compression stroke cylinder to start the engine without an aid of a starter.
    Type: Application
    Filed: July 15, 2005
    Publication date: January 26, 2006
    Applicant: Denso Corporation
    Inventors: Nobuyuki Satake, Seiichirou Nishikawa, Yoshifumi Murakami
  • Publication number: 20050228575
    Abstract: An engine stopping and starting control device includes a prediction means, a control means, and a start control means. The prediction means predicts a cylinder on a compression stroke upon a stop during a process for stopping an engine. The control means controls a fuel injection upon a stop that injects fuel into the cylinder during the process for stopping the engine to seal an air-fuel mixture therein. The start control means fires the cylinder to generate a first explosion to start the engine.
    Type: Application
    Filed: April 7, 2005
    Publication date: October 13, 2005
    Applicant: DENSO CORPORATION
    Inventors: Yoshifumi Murakami, Seiichirou Nishikawa
  • Publication number: 20050103111
    Abstract: A pressure sensor for detecting a pressure such as a brake oil pressure in an automobile is composed of a cylindrical stem, a sensor chip and a circuit board for processing an electrical signal from the sensor chip. The cylindrical stem includes a thin diaphragm formed at an axial end and an opening formed at the other axial end. The sensor chip is mounted on the diaphragm, and the circuit board is mounted on a flat side surface formed on the outer periphery of the cylindrical stem so that the circuit board is positioned perpendicularly to the sensor chip, thereby reducing a size of the pressure sensor in the radial direction of the stem. The pressure to be detected is introduced into the cylindrical stem from its opening, and the pressure is detected by the sensor chip mounted on the diaphragm.
    Type: Application
    Filed: October 26, 2004
    Publication date: May 19, 2005
    Inventors: Masahito Imai, Yoshifumi Murakami
  • Publication number: 20040149251
    Abstract: A control apparatus for an engine increases an intake air quantity just before engine stop to increase a compression pressure in a compression stroke. As the compression pressure is increased, a negative torque in the compression stroke increases and obstructs engine rotation, and brakes the engine rotation. Thus, a range of crank angle, in which torque is below engine friction, that is, in which engine rotation can be stopped, is reduced. As a result, variation in engine rotation stop position is reduced to be within a small range of crank angle. Information of engine rotation stop position is stored, and the stored information of engine rotation stop position is used at the start of an engine to accurately determine an initial injection cylinder and an initial ignition cylinder to start the engine.
    Type: Application
    Filed: January 22, 2004
    Publication date: August 5, 2004
    Applicant: DENSO CORPORATION
    Inventors: Seiichirou Nishikawa, Yoshifumi Murakami
  • Patent number: 6591689
    Abstract: A pressure sensor has a sensor chip with a diaphragm formed therein and bumps formed thereon, and a stem with leads extending from a surface thereof to the sensor chip. The bumps and the leads are electrically connected by face down bonding so that a surface of the sensor chip faces the surface of the stem. In this manner, bonding wires are unnecessary. Therefore, an area for disposing the bonding wires in the stem can be cut down, so that the pressure sensor can be miniaturized.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: July 15, 2003
    Assignee: Denso Corporation
    Inventors: Akira Nidan, Takafumi Taki, Hideaki Hara, Michihiro Masuda, Kaname Ban, Kazuo Tanaka, Yoshifumi Murakami
  • Patent number: 6422088
    Abstract: A reference voltage generating circuit is constituted by resistors RE and RF each having a resistance not influenced by an application of pressure. The reference voltage generating circuit is connected between one and the other ends of a bridge circuit. A failure judgement of the bridge circuit is performed based on a comparison of a voltage difference VBC between two midpoints B and C of the bridge circuit and voltage differences VCE and VBE between a reference voltage level of the reference voltage generating circuit and the voltage levels of two midpoints B and C.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: July 23, 2002
    Assignee: Denso Corporation
    Inventors: Nobukazu Oba, Yoshifumi Murakami, Yukihiko Tanizawa, Hiroaki Tanaka, Seiichiro Ishio, Inao Toyoda, Yasutoshi Suzuki
  • Patent number: 6401018
    Abstract: A sensor device includes a sensor circuit for measuring a physical amount such as pressure, a voltage detector for detecting a voltage actually supplied to the sensor circuit, and an oscillator for generating an oscillating signal when the voltage detector finds the voltage supplied to the sensor circuit is abnormally low. The sensor signal and the oscillating signal are selectively supplied to a controller. The controller controls various devices connected thereto based on the sensor signal, while it detects a malfunction of the sensor device based on either a high level signal or a low level signal in the oscillating signal. Thus, the malfunction of the sensor device is automatically detected without fail.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: June 4, 2002
    Assignee: Denso Corporation
    Inventors: Nobukazu Oba, Yoshifumi Murakami
  • Patent number: 6343498
    Abstract: A sensor apparatus which can accurately detect a fault due to poor connection or the like at a connection portion between a sensor portion and a control portion. The sensor apparatus is provided with a sensor portion and a control portion which is electrically connected to the sensor portion via a power supply line, an output line and a ground line. The control portion includes a switch and the diagnosis circuit. The switch switches the power supply to the sensor portion to one of the power supply line and the output line. When the power is supplied to the output line, the diagnosis circuit measures current flowing from the output line to the ground line, and detects the fault by comparing the measured current with a reference voltage value.
    Type: Grant
    Filed: October 12, 2000
    Date of Patent: February 5, 2002
    Assignee: Denso Corporation
    Inventors: Nobukazu Oba, Makoto Hatanaka, Yoshifumi Murakami
  • Publication number: 20020005072
    Abstract: A pressure sensor has a sensor chip with a diaphragm formed therein and bumps formed thereon, and a stem with leads extending from a surface thereof to the sensor chip. The bumps and the leads are electrically connected by face down bonding so that a surface of the sensor chip faces the surface of the stem. In this manner, bonding wires are unnecessary. Therefore, an area for disposing the bonding wires in the stem can be cut down, so that the pressure sensor can be miniaturized.
    Type: Application
    Filed: June 29, 2001
    Publication date: January 17, 2002
    Inventors: Akira Nidan, Takafumi Taki, Hideaki Hara, Michihiro Masuda, Kaname Ban, Kazuo Tanaka, Yoshifumi Murakami