Patents by Inventor Tatsuhiko Takahashi
Tatsuhiko Takahashi 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: 6761139Abstract: An actuator for changing a relative position of at least an intake or exhaust camshaft, and a crank shaft; a cylinder identifying unit for performing cylinder identification in accordance with results detected by a crank angle sensor and a cam angle sensor; a valve timing detecting unit for detecting valve timing in accordance with the results detected by the crank angle sensor and the cam angle sensor; and an OCV for controlling the actuator based on a value detected by the valve timing detecting unit are provided. Control is performed at a neutral point by a valve timing controlling unit when the cylinder identification by the cylinder identifying unit is in an indefinite state.Type: GrantFiled: April 30, 2003Date of Patent: July 13, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Shiro Yonezawa, Yasuyoshi Hori, Hideki Hagari, Akira Furuta
-
Patent number: 6758176Abstract: Valve timing control apparatus for engine includes a cam phase actuator (1113) composed of a first rotor (1) rotatable with a crank shaft, a second rotor (6) mounted on a cam shaft (7) and a lock mechanism (15, 16, 18) for locking the second rotor to the first rotor, a pump (1118) for generating a hydraulic pressure, an ECU for computing a current value corresponding to a pressure for clearing a locked state at the first relative angle for shifting the first relative angle to a second angle, and an OCV (1114) for supplying a pressure for regulating a cam phase of the second rotor in dependence on the current value. The ECU computes a first current value for generating a first pressure for releasing the locked state. The first current value is supplied to the OCV for a predetermined time before shifting the first relative angle.Type: GrantFiled: October 28, 2002Date of Patent: July 6, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Koji Wada, Tatsuhiko Takahashi
-
Patent number: 6732689Abstract: A valve timing control apparatus for an engine. Presence/absence of a torque demand (xtq) is estimated upon starting of a lock pin release control to thereby alter a change rate (&bgr;) of a target phase angle in dependence on presence/absence of the torque demand (xtq). Unless torque demand is issued, the change rate is set to a small value (&bgr;2) for suppressing the change of the target phase angle (&thgr;t) after detection of release of the lock pin in order to avoid a shock unexpected by a driver. When the torque demand is issued, the change rate is set to a large value (&bgr;1) for allowing the target phase angle to approach speedily to a base target phase angle (&thgr;map) for thereby minimizing a delay in response involved in the phase angle detection through the lock pin release control.Type: GrantFiled: October 28, 2002Date of Patent: May 11, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Koji Wada, Tatsuhiko Takahashi
-
Publication number: 20040083800Abstract: The present invention has: a crank signal vane in which teeth are provided on a circumference at predetermined crank angles, and a first missing tooth portion having one missing tooth and a second missing tooth portion having two missing teeth are established; a crank angle sensor for outputting a pulse shape crank signal pattern corresponding to the teeth; and an electronic control unit for calculating a crank signal period based on the crank signal pattern, computing a missing tooth identification value based on the calculated crank signal period; detecting the number of missing teeth based on the computed missing tooth identification value, detecting a crank angle reference position for cases in which the detected number of missing teeth is one or two, and identifying a cylinder group.Type: ApplicationFiled: May 9, 2003Publication date: May 6, 2004Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Shiro Yonezawa, Akira Furuta, Yasuyoshi Hori, Hideki Hagari, Tatsuhiko Takahashi
-
Patent number: 6715470Abstract: Disclosed is a fuel supply device for an internal combustion engine, which is capable of preventing fuel pressure control problems caused by divergence of a feedback control amount in pump control. A target fuel pressure is computed, and a pump discharge quantity is computed as a feed forward quantity in accordance with an amount of change in the target fuel pressure. A determination is made as to whether or not the feed forward quantity is zero, and when the feed forward quantity is zero, a feedback correction quantity is computed based on the target fuel pressure and the actual fuel pressure, and feedback control is performed. In the case where the feed forward quantity is not zero, the computation of the feedback correction quantity is stopped and the feed forward control is continued.Type: GrantFiled: June 27, 2002Date of Patent: April 6, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Tatsuhiko Takahashi
-
Publication number: 20040011311Abstract: A valve timing control apparatus for an internal combustion engine can be improved in accuracy in the detection of valve timing (cam angles). A crank angle sensor generates a crank angle signal in the form of a train of pulses. Cam angle changing parts change phases of camshafts relative to a crankshaft. Cam angle sensors generate cam angle signals. A reference crank angle detection part detects reference crank angles based on the crank angle signal. Cam angle calculation parts calculate the cam angles of the camshafts based on the crank angle signal and the cam angle signals. A cam angle control part controls the relative phases of the camshafts to the crankshaft so as make them coincide with target cam angles corresponding to operating conditions of the engine. A cam angle calculation part calculates the cam angles by counting the number of pulses of the crank angle signal.Type: ApplicationFiled: December 6, 2002Publication date: January 22, 2004Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventor: Tatsuhiko Takahashi
-
Publication number: 20040000190Abstract: A cylinder identifying apparatus has a generator which generates a cylinder discrimination signal, a generator which generates a crank angle position signal, and a control unit which obtains the number of detections of the crank angle position signal, the number of detections of the cylinder discrimination signal, the number of detections of the crank angle position signal at the time of detection of the cylinder discrimination signal, etc. The control unit sets a cylinder discrimination period B35° to B75° CA if the present reference crank position is a first-time detection result after startup, sets a cylinder discrimination period B75° to B75° CA if the present reference crank position is a second-time or some other subsequent detection result, obtains the number of detections of the cylinder discrimination signal, and identifies a cylinder on the basis of the number of pulse dropouts and the number of detections of the cylinder discrimination signal.Type: ApplicationFiled: December 3, 2002Publication date: January 1, 2004Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Yasuyoshi Hori, Shiro Yonezawa, Akira Furuta, Hideki Hagari, Tatsuhiko Takahashi
-
Publication number: 20030226533Abstract: The valve timing control system of the present invention comprises an actuator for changing an actual valve timing of an intake valve or an exhaust valve; an oil pressure adjusting unit for supplying operating oil to the actuator, and adjusting the oil pressure thereof; an actual valve timing control unit for controlling the actuator by controlling the oil pressure adjusting unit, so that the actual valve timing follows up a target value; and an oil temperature estimation unit for estimating the temperature of the operating oil, according to an operating state of the internal combustion engine from a previous operation, and according to its current operating state. Based on the estimated oil temperature, the actual valve timing control unit switches a control amount for controlling the oil pressure adjusting unit.Type: ApplicationFiled: April 24, 2003Publication date: December 11, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Morio Fujiwara, Tatsuhiko Takahashi, Koji Wada
-
Publication number: 20030226529Abstract: An actuator for changing a relative position of at least an intake or exhaust camshaft, and a crank shaft; a cylinder identifying unit for performing cylinder identification in accordance with results detected by a crank angle sensor and a cam angle sensor; a valve timing detecting unit for detecting valve timing in accordance with the results detected by the crank angle sensor and the cam angle sensor; and an OCV for controlling the actuator based on a value detected by the valve timing detecting unit are provided. Control is performed at a neutral point by a valve timing controlling unit when the cylinder identification by the cylinder identifying unit is in an indefinite state.Type: ApplicationFiled: April 30, 2003Publication date: December 11, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Tatsuhiko Takahashi, Shiro Yonezawa, Yasuyoshi Hori, Hideki Hagari, Akira Furuta
-
Patent number: 6644273Abstract: An internal combustion engine control apparatus can reliably detect abnormality in a crank angle position signal to ensure a fail safe function upon occurrence of the abnormally. A fuel injection signal and an ignition signal is generated based on the result of cylinder identification performed by a cylinder identification part and the crank angle position of the crank angle position signal. An abnormality determination part determines whether the crank angle position signal is abnormal. The cylinder identification part includes a cylinder identification resetting part for resetting the current content of the cylinder identification performed by the cylinder identification part upon determination of abnormality.Type: GrantFiled: December 3, 2002Date of Patent: November 11, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Hideki Hagari, Yasuyoshi Hori, Akira Furuta, Tatsuhiko Takahashi, Shiro Yonezawa
-
Publication number: 20030200943Abstract: A valve timing control apparatus for an engine. Presence/absence of a torque demand (xtq) is estimated upon starting of a lock pin release control to thereby alter a change rate (&bgr;) of a target phase angle in dependence on presence/absence of the torque demand (xtq). Unless torque demand is issued, the change rate is set to a small value (&bgr;2) for suppressing the change of the target phase angle (&thgr;t) after detection of release of the lock pin in order to avoid a shock unexpected by a driver. When the torque demand is issued, the change rate is set to a large value (&bgr;1) for allowing the target phase angle to approach speedily to a base target phase angle (&thgr;map) for thereby minimizing a delay in response involved in the phase angle detection through the lock pin release control.Type: ApplicationFiled: October 28, 2002Publication date: October 30, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Koji Wada, Tatsuhiko Takahashi
-
Publication number: 20030200944Abstract: Valve timing control apparatus for internal combustion engine includes a cam phase actuator (1113) composed of a first rotor (1) rotatable with a crank, a second rotor (6) fixed on a cam shaft (7) for actuating an intake or exhaust valve, and a lock mechanism (15, 16, 17, 18) for locking the second rotor to the first rotor at a first angle, a pump (1118) for generating a hydraulic pressure, an ECU (1117) for determining a current value for releasing a locked state at the first angle for shifting to a second angle, and an oil control valve (1114) for regulating a cam phase of the second rotor. The ECU determines a locked state or an unlocked state of the lock mechanism to allow the second rotor to be released from being locked to the first rotor when the lock mechanism is in the locked state.Type: ApplicationFiled: October 28, 2002Publication date: October 30, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Tatsuhiko Takahashi, Koji Wada
-
Publication number: 20030196622Abstract: Valve timing control apparatus for engine includes a cam phase actuator (1113) composed of a first rotor (1) rotatable with a crank shaft, a second rotor (6) mounted on a cam shaft (7) and a lock mechanism (15, 16, 18) for locking the second rotor to the first rotor, a pump (1118) for generating a hydraulic pressure, an ECU for computing a current value corresponding to a pressure for clearing a locked state at the first relative angle for shifting the first relative angle to a second angle, and an OCV (1114) for supplying a pressure for regulating a cam phase of the second rotor in dependence on the current value. The ECU computes a first current value for generating a first pressure for releasing the locked state. The first current value is supplied to the OCV for a predetermined time before shifting the first relative angle.Type: ApplicationFiled: October 28, 2002Publication date: October 23, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Koji Wada, Tatsuhiko Takahashi
-
Publication number: 20030127082Abstract: Disclosed is a fuel supply device for an internal combustion engine, which is capable of preventing fuel pressure control problems caused by divergence of a feedback control amount in pump control. A target fuel pressure is computed, and a pump discharge quantity is computed as a feed forward quantity in accordance with an amount of change in the target fuel pressure. A determination is made as to whether or not the feed forward quantity is zero, and when the feed forward quantity is zero, a feedback correction quantity is computed based on the target fuel pressure and the actual fuel pressure, and feedback control is performed. In the case where the feed forward quantity is not zero, the computation of the feedback correction quantity is stopped and the feed forward control is continued.Type: ApplicationFiled: June 27, 2002Publication date: July 10, 2003Applicant: MITSUBISHI DENKI KABUSHIKI KAISHAInventor: Tatsuhiko Takahashi
-
Patent number: 6561147Abstract: A valve timing control system for an internal combustion engine for preventing hitching of a lock pin of an actuator at the time of changing a cam angle is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators in dependence on engine operation states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position, and an unlocking mechanism for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller executes a releasing operation of the locking mechanism if the lock-up position in the locking mechanism changes from inside a predetermined range to outside the predetermined range.Type: GrantFiled: October 23, 2001Date of Patent: May 13, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Morio Fujiwara
-
Patent number: 6526930Abstract: A valve timing control system for an internal combustion engine for preventing dispersion of a control amount and unexpected release of a lock pin is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators in dependence on engine operation states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position, and an unlocking mechanism for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller makes a limit of control range small when the controller drives the locking mechanism to control the relative phase within a predetermined range of the lock-up position.Type: GrantFiled: October 22, 2001Date of Patent: March 4, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Morio Fujiwara
-
Patent number: 6520131Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode while enhancing control accuracy by learning a reference position of a cam angle. The system includes actuators (15; 16) coupled to cam shafts (15C; 16C), respectively, hydraulic pressure supply means (19; 20) for driving the actuators (15; 16), and a controller (21A) for controlling hydraulic pressure fed to the actuators (15; 16) in dependence on engine operation states to change phases of the cam shafts (15C; 16C) relative to a crank shaft (13C). The controller (21A) is so designed as to set a valve timing to a most advanced position or alternatively to a most retarded position in a cold-state idling operation mode for the purpose of learning a reference position.Type: GrantFiled: July 26, 2001Date of Patent: February 18, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Morio Fujiwara, Koji Wada
-
Patent number: 6516759Abstract: A valve timing control apparatus for an internal combustion engine is capable of ensuring good response within a control range, stability outside the control range, and durability without increasing the capacity of electric power for a drive circuit and an OCV coil. The valve timing control apparatus includes an intake vale 31, an exhaust valve 32, an engine operating condition detecting section (3, 11, 14), a target valve timing calculating section 21, variable valve timing mechanisms 15, 16, an actual valve timing detecting section (14, 17, 18), a control amount calculating section 21 for calculating a control amount based on target valve timing, actual valve timing and engine operating conditions, and an actual valve timing control section (19, 20) for outputting the control amount as an output control amount to the variable valve timing mechanisms.Type: GrantFiled: June 25, 2001Date of Patent: February 11, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Morio Fujiwara
-
Patent number: 6513468Abstract: A valve timing control system for an internal combustion engine for preventing dispersion of a control amount and unexpected unlocking of a lock pin is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators depending on operating states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position and unlocking mechanisms for unlocking the locking mechanism in response to a predetermined hydraulic pressure, and the controller restricts a control of valve timing within a predetermined range of said lock-up position in the locking mechanism.Type: GrantFiled: October 22, 2001Date of Patent: February 4, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Morio Fujiwara
-
Patent number: 6499450Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode. The system includes actuators (15, 16) coupled to cam shafts (15C, 16C), hydraulic pressure supply units (19, 20) for driving the actuators (15; 16), and a controller (21A) for controlling a hydraulic pressure for the actuators (15, 16) in dependence on engine operation states to change phase of the cam shafts (15C; 16C) relative to a crank shaft. The actuator (15; 16) includes a locking mechanism (155, 157) for setting the relative phase to a lock-up position, and an unlocking mechanism (156) for releasing the locking mechanism in En response to a predetermined hydraulic pressure. The controller (21A) sets the relative phase to the lock-up position in a starting operation, while controlling the relative phase to be advanced in an engine state succeeding to the starting operation.Type: GrantFiled: June 28, 2001Date of Patent: December 31, 2002Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Tatsuhiko Takahashi, Atsuko Hashimoto, Hirofumi Ohuchi