Patents by Inventor Seinosuke Hara

Seinosuke Hara 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: 7461620
    Abstract: A valve actuating link is provided for transmitting a combined movement of a drive cam on a cam shaft and a control cam on a control shaft to a valve pressing structure of an engine valve. The valve actuating link comprises a bearing portion that bears the control shaft, a hook-shaped lower portion that surrounds the cam shaft keeping a given space therebetween and a cam portion that repeatedly pushes the valve pressing structure to induce an open/close operation of the engine valve. Each of a plurality of engine valves has its own respective drive cam, control cam, valve actuating link and valve pressing structure.
    Type: Grant
    Filed: January 17, 2007
    Date of Patent: December 9, 2008
    Assignee: Hitachi, Ltd.
    Inventor: Seinosuke Hara
  • Publication number: 20080141961
    Abstract: A variable valve system for an internal combustion engine includes a drive shaft rotated by an engine crankshaft, a drive cam integrally mounted on the drive shaft, first and second swing cams mounted on first and second engine valves in each engine cylinder, a valve lift mechanism for converting a rotational movement of the drive cam into swing movements of the first and second swing cams to open and close the first and second engine valves, and a control mechanism for controlling the operating position of the valve lift mechanism to vary the valve lifts of the first and second engine valves according to engine operating conditions. The valve lifts of the first and second engine valves are different from each other when the control mechanism performs minimum lift control on the valve lift mechanism to control the valve lifts of the first and second engine valves to minimum lifts.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 19, 2008
    Inventors: Seinosuke Hara, Makoto Nakamura
  • Patent number: 7331323
    Abstract: A lubricating oil supplying system for an internal combustion engine includes a lubricating oil storage section for storing lubricating oil. A driven pump is driven by the internal combustion engine to suck the lubricating oil from the lubricating oil storage section and discharge the lubricating oil to a discharge passage. An electric pump is provided for sucking the lubricating oil discharged from the driven pump to the discharge passage and discharge the lubricating oil to a lubricating oil requiring section in the internal combustion engine. A controlling mechanism is provided for drivingly controlling the electric pump in accordance with a control signal. A bypass passage is provided for bypassing the driven pump. A check valve is disposed in the bypass passage to allow the lubricating oil in the lubricating oil storage section to flow only through a path bypassing the driven pump and toward the discharge passage.
    Type: Grant
    Filed: October 3, 2005
    Date of Patent: February 19, 2008
    Assignee: Hitachi, Ltd.
    Inventor: Seinosuke Hara
  • Patent number: 7322324
    Abstract: In a valve operating apparatus of an engine capable of varying a valve lift characteristic, rotary motion of a drive cam is converted through a motion-conversion linkage including a rocker arm into oscillating motion of a valve actuation member for operating an engine valve. Also provided is a control shaft whose angular position is adjusted depending on an engine operating condition for changing a linkage attitude. The valve actuation member has an arcuate portion curved to bypass the drive shaft. The control shaft has a coaxial shaft portion and an eccentric control cam. The control cam is a fulcrum of oscillating motion of the rocker arm and the coaxial shaft portion of the control shaft is a fulcrum of oscillating motion of the valve actuation member. The fulcrums are laid out in close proximity to each other.
    Type: Grant
    Filed: June 22, 2006
    Date of Patent: January 29, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Seinosuke Hara, Makoto Nakamura
  • Publication number: 20070283911
    Abstract: A variable valve actuating apparatus for an internal combustion engine includes a first valve actuating mechanism to vary a first valve operating condition, and a second valve actuating mechanism to vary a second valve operating condition. A controller controls the first valve actuating mechanism to satisfy a predetermined engine starting condition before a start of a cranking operation or during the cranking operation, with respect to an engine operating condition including the second valve operating condition controlled by the second valve actuating mechanism.
    Type: Application
    Filed: June 8, 2007
    Publication date: December 13, 2007
    Inventors: Makoto Nakamura, Seinosuke Hara
  • Patent number: 7305946
    Abstract: A variable valve operating apparatus including a drive cam, a rocker cam pivotally supported on a first pivot, a lift varying mechanism operative to change a pivotal position of the rocker cam to vary a valve lift of an engine valve, a swing arm including one end portion at which the swing arm is pivotally supported on a second pivot and the other end portion contacted with the engine valve, a hollow space defined between the end portions of the swing arm, and a driven roller rotatably disposed within the hollow space of the swing arm and contacted with a cam surface of the rocker cam. When the valve lift of the engine valve is a predetermined lift amount or more, a contact point between the driven roller and the rocker cam is located in the hollow space of the swing arm.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: December 11, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Nakamura, Seinosuke Hara
  • Publication number: 20070277755
    Abstract: A variable valve operating apparatus including a drive cam, a rocker cam swingably moveable about the swing axis so as to move an engine valve to open and closing positions, a motion transmission mechanism operative to convert a rotational motion of the drive cam to a swing motion of the rocker cam, and a control shaft operative to control an attitude of the motion transmission mechanism to vary a valve lift of the engine valve. A roller or a follower portion are disposed on one end portion of the motion transmission mechanism on a side of the drive cam and contacted with the drive cam. A biasing member is arranged to bias the roller onto the drive cam through a roller shaft or biases the follower portion onto the drive cam through a support for the biasing member.
    Type: Application
    Filed: May 25, 2007
    Publication date: December 6, 2007
    Inventors: Makoto Nakamura, Seinosuke Hara, Akira Hidaka, Mikihiro Kajiura
  • Publication number: 20070175424
    Abstract: A valve operating apparatus for an internal combustion engine including a drive cam, first and second swing cams, first and second motion transmission mechanisms and first and second valve actuating members. The first and second swing cams are provided with identical swing motion characteristic with respect to a rotation angle of the drive cam through the first and second motion transmission mechanisms. The first swing cam and the first valve actuating member cooperate with each other to provide a valve lift amount of the engine valve for the first group of cylinders with respect to a swing angle of the first swing cam which is identical to a valve lift amount of the engine valve for the second group of cylinders with respect to a swing angle of the second swing cam.
    Type: Application
    Filed: February 1, 2007
    Publication date: August 2, 2007
    Applicant: HITACHI, LTD.
    Inventors: Makoto Nakamura, Mikihiro Kajiura, Yoshihiko Yamada, Seinosuke Hara
  • Patent number: 7246578
    Abstract: A valve operating mechanism of an internal combustion engine, comprises a drive cam rotatable with and eccentric to a drive shaft; a link arm having a circular opening in which the drive cam is rotatably received, so that rotation of drive cam about an axis of the drive shaft produces a swing movement of the link arm; a pair of swing cams swingably disposed on the drive shaft at both sides of the drive cam, the swing cams being connected through a movement transmission mechanism to the link arm to be swung when the link arm is subjected to the swing movement; a pair of swing arms respectively actuated by the swing cams for carrying out an open/close operation of a pair of engine valves; a pair of spring retainers respectively provided by the pair of engine valves; and a pair of valve springs respectively held by the spring retainers and biasing the engine valves in a close direction. A lubricating oil passage is formed in the drive cam.
    Type: Grant
    Filed: February 11, 2005
    Date of Patent: July 24, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Nakamura, Mikihiro Kajiura, Seinosuke Hara
  • Patent number: 7240649
    Abstract: A rocker arm is swingably supported by a control shaft that has an eccentric control cam formed thereon. The rocker arm is swung by a torque of a crankshaft of the engine. Two swing cams are swingably supported by a drive shaft and actuate respective engine valves to make an open/close operation of the same by receiving the swinging movement from the rocker arm. The rocker arm comprises a cylindrical base portion through which the control shaft passes; a first projected end that is provided at a first radially outside part of the cylindrical base portion in the vicinity of one axial end of the cylindrical base portion, the first projected end receiving the torque from the crankshaft for carrying out the pivotal movement of the rocker arm; and two second projected ends that are spaced from each other and provided at a second radially outside part of the cylindrical base portion, the second projected ends actuating the two swing cams when the rocker arm is swung.
    Type: Grant
    Filed: May 5, 2006
    Date of Patent: July 10, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Seinosuke Hara, Makoto Nakamura
  • Publication number: 20070144473
    Abstract: In a variable valve actuation system of an internal combustion engine employing a variable valve actuator capable of variably adjusting at least intake valve closure timing depending on engine operating conditions, a processor of a control unit is programmed to phase-advance the intake valve closure timing to a predetermined timing value after a piston top dead center position and before a piston bottom dead center position on intake stroke during at least one of an engine starting period and an engine stopping period. The variable valve actuator includes a biasing device by which the intake valve closure timing is permanently biased toward the predetermined timing value.
    Type: Application
    Filed: November 14, 2006
    Publication date: June 28, 2007
    Inventors: Makoto Nakamura, Seinosuke Hara
  • Publication number: 20070113810
    Abstract: A valve actuating link is provided for transmitting a combined movement of a drive cam on a cam shaft and a control cam on a control shaft to a valve pressing structure of an engine valve. The valve actuating link comprises a bearing portion that bears the control shaft, a hook-shaped lower portion that surrounds the cam shaft keeping a given space therebetween and a cam portion that repeatedly pushes the valve pressing structure to induce an open/close operation of the engine valve. Each of a plurality of engine valves has its own respective drive cam, control cam, valve actuating link and valve pressing structure.
    Type: Application
    Filed: January 17, 2007
    Publication date: May 24, 2007
    Inventor: Seinosuke Hara
  • Publication number: 20070089697
    Abstract: In a control apparatus for controlling a variable valve actuation system employed in an internal combustion engine, engine/vehicle sensors are provided to detect at least a cylinder pressure in an engine cylinder for monitoring a change of state in combustion, arising from fluctuations in states/characteristics of air-fuel mixture such as a change in fuel property. Also provided is a control system that controls the variable valve actuation system responsively to a manipulated variable modified based on the cylinder pressure reflecting the change of state in combustion by a model of combustion.
    Type: Application
    Filed: October 11, 2006
    Publication date: April 26, 2007
    Inventors: Seinosuke Hara, Tomio Hokari, Makoto Nakamura
  • Publication number: 20070074702
    Abstract: In a multi-stage fuel-injection internal combustion engine employing a fuel injection system and a variable valve actuation system, engine valve timings are variably controlled depending on engine operating conditions. An electronic engine control unit is configured to execute cooperative control of the timing of sub-injection, injected before main injection, responsively to intake valve closure timing, and also to execute cooperative control of the timing of sub-injection, injected after the-main injection, responsively to exhaust valve open timing.
    Type: Application
    Filed: September 14, 2006
    Publication date: April 5, 2007
    Inventors: Makoto Nakamura, Tomio Hokari, Seinosuke Hara, Seiji Suga, Masahiko Watanabe
  • Patent number: 7188595
    Abstract: A valve actuating link is provided for transmitting a combined movement of a drive cam on a cam shaft and a control cam on a control shaft to a valve pressing structure of an engine valve. The valve actuating link comprises a bearing portion that bears the control shaft, a hook-shaped lower portion that surrounds the cam shaft keeping a given space therebetween and a cam portion that repeatedly pushes the valve pressing structure to induce an open/close operation of the engine valve.
    Type: Grant
    Filed: August 30, 2005
    Date of Patent: March 13, 2007
    Assignee: Hitachi, Ltd.
    Inventor: Seinosuke Hara
  • Publication number: 20060288972
    Abstract: In a valve operating apparatus of an engine capable of varying a valve lift characteristic, rotary motion of a drive cam is converted through a motion-conversion linkage including a rocker arm into oscillating motion of a valve actuation member for operating an engine valve. Also provided is a control shaft whose angular position is adjusted depending on an engine operating condition for changing a linkage attitude. The valve actuation member has an arcuate portion curved to bypass the drive shaft. The control shaft has a coaxial shaft portion and an eccentric control cam. The control cam is a fulcrum of oscillating motion of the rocker arm and the coaxial shaft portion of the control shaft is a fulcrum of oscillating motion of the valve actuation member. The fulcrums are laid out in close proximity to each other.
    Type: Application
    Filed: June 22, 2006
    Publication date: December 28, 2006
    Inventors: Seinosuke Hara, Makoto Nakamura
  • Publication number: 20060272608
    Abstract: In a compression ignition engine employing a variable valve actuation mechanism variably adjusting an intake valve characteristic including at least one of an intake valve lift and an intake valve closure timing, a control system operates to temporarily lower an effective compression ratio of the engine by controlling the intake valve characteristic during a cranking period of cold starting operation. At a point of time when a predetermined cranking speed threshold value has been reached owing to a cranking speed rise, the effective compression ratio is risen by controlling the intake valve characteristic. After combustion of the engine has been stabilized, the intake valve characteristic is brought closer to a desired value determined based on engine operating conditions by way of closed-loop control.
    Type: Application
    Filed: June 6, 2006
    Publication date: December 7, 2006
    Inventors: Seinosuke Hara, Tomio Hokari, Seiji Suga, Makoto Nakamura, Masahiko Watanabe
  • Publication number: 20060254546
    Abstract: A rocker arm is swingably supported by a control shaft that has an eccentric control cam formed thereon. The rocker arm is swung by a torque of a crankshaft of the engine. Two swing cams are swingably supported by a drive shaft and actuate respective engine valves to make an open/close operation of the same by receiving the swinging movement from the rocker arm. The rocker arm comprises a cylindrical base portion through which the control shaft passes; a first projected end that is provided at a first radially outside part of the cylindrical base portion in the vicinity of one axial end of the cylindrical base portion, the first projected end receiving the torque from the crankshaft for carrying out the pivotal movement of the rocker arm; and two second projected ends that are spaced from each other and provided at a second radially outside part of the cylindrical base portion, the second projected ends actuating the two swing cams when the rocker arm is swung.
    Type: Application
    Filed: May 5, 2006
    Publication date: November 16, 2006
    Inventors: Seinosuke Hara, Makoto Nakamura
  • Publication number: 20060236960
    Abstract: In a variably operated valve system for a compression ignition engine, an adjustment mechanism is controlled by means of a control section to detach an intake valve closure timing from a bottom dead center in accordance with an engine driving condition, and an engine start securing section guarantees an engine start even at least one of cases during a failure in the control section, during a stop of the engine, and during a start of the engine.
    Type: Application
    Filed: March 6, 2006
    Publication date: October 26, 2006
    Inventors: Makoto Nakamura, Seinosuke Hara, Seiji Suga, Masahiko Watanabe, Tomio Hokari
  • Publication number: 20060112917
    Abstract: A variable valve operating apparatus including a drive cam, a rocker cam pivotally supported on a first pivot, a lift varying mechanism operative to change a pivotal position of the rocker cam to vary a valve lift of an engine valve, a swing arm including one end portion at which the swing arm is pivotally supported on a second pivot and the other end portion contacted with the engine valve, a hollow space defined between the end portions of the swing arm, and a driven roller rotatably disposed within the hollow space of the swing arm and contacted with a cam surface of the rocker cam. When the valve lift of the engine valve is a predetermined lift amount or more, a contact point between the driven roller and the rocker cam is located in the hollow space of the swing arm.
    Type: Application
    Filed: October 13, 2005
    Publication date: June 1, 2006
    Inventors: Makoto Nakamura, Seinosuke Hara