Patents by Inventor Kei Kitajima
Kei Kitajima 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).
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Patent number: 8641578Abstract: In a controller of a vehicle drive unit that is one embodiment of the present invention, a plurality of slippage control regions (regions A to C) are set based on the timing of booming noise generation that accompanies engine driving (time from when the vehicle running state enters a region until booming noise is generated) so as to actively use, for example, regions B and C where booming noise is generated if the road load comes to a balance due to a slope or the like and running is then continued and where booming noise is not immediately generated even after the vehicle running state enters the regions, so the frequency of performing lockup slippage control is increased and the fuel saving effects of the lockup slippage control are enhanced.Type: GrantFiled: September 24, 2009Date of Patent: February 4, 2014Assignee: Toyota Jidosha Kabushiki KaishaInventors: Kei Kitajima, Hitoshi Matsunaga
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Patent number: 8565987Abstract: A shift controller for an automatic transmission capable of automatically shifting up in a manual mode is provided. In the shift controller, a hysteresis between an automatic upshift line and a downshift permission line is set to be smaller as the accelerator opening degree decreases. As a result, when the accelerator opening degree is larger and therefore hunting is more likely to occur, it is possible to avoid an excessively small time interval between a downshift and an upshift. On the other hand, when the accelerator opening degree is smaller and therefore hunting is less likely to occur, a manual downshift permission region can be expanded to a higher rotational speed region, whereby a driver's manual downshift request can be satisfied in a higher vehicle speed region.Type: GrantFiled: September 13, 2012Date of Patent: October 22, 2013Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hitoshi Matsunaga, Kei Kitajima
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Patent number: 8489292Abstract: A downshift allowable vehicle speed is variably set according to a torque converter slippage amount. Specifically, a downshift allowable vehicle speed is variably set by, using a reference downshift allowable vehicle speed when the torque converter slippage amount is 0 and a gear ratio of the automatic transmission after a downshift, calculating an allowable vehicle speed correction amount based on the present torque converter slippage amount and the gear ratio after the downshift, and setting a value obtained by subtracting the allowable vehicle speed correction amount from the reference downshift allowable vehicle speed as the downshift allowable vehicle speed. By such setting, it is possible to set a higher downshift allowable vehicle speed as the torque converter slippage amount becomes smaller, so it is possible to expand a downshift allowable region when the manual gearshift mode is selected.Type: GrantFiled: October 29, 2009Date of Patent: July 16, 2013Assignee: Toyota Jidosha Kabushika KaishaInventors: Hitoshi Matsunaga, Kei Kitajima
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Publication number: 20130012356Abstract: A shift controller for an automatic transmission capable of automatically shifting up in a manual mode is provided. In the shift controller, a hysteresis between an automatic upshift line and a downshift permission line is set to be smaller as the accelerator opening degree decreases. As a result, when the accelerator opening degree is larger and therefore hunting is more likely to occur, it is possible to avoid an excessively small time interval between a downshift and an upshift. On the other hand, when the accelerator opening degree is smaller and therefore hunting is less likely to occur, a manual downshift permission region can be expanded to a higher rotational speed region, whereby a driver's manual downshift request can be satisfied in a higher vehicle speed region.Type: ApplicationFiled: September 13, 2012Publication date: January 10, 2013Applicant: Toyota Jidosha Kabushiki KaishaInventors: Hitoshi Matsunaga, Kei Kitajima
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Patent number: 8332107Abstract: A shift controller for an automatic transmission capable of automatically shifting up in a manual mode is provided. In the shift controller, a hysteresis between an automatic upshift line and a downshift permission line is set to be smaller as the accelerator opening degree decreases. As a result, when the accelerator opening degree is larger and therefore hunting is more likely to occur, it is possible to avoid an excessively small time interval between a downshift and an upshift. On the other hand, when the accelerator opening degree is smaller and therefore hunting is less likely to occur, a manual downshift permission region can be expanded to a higher rotational speed region, whereby a driver's manual downshift request can be satisfied in a higher vehicle speed region.Type: GrantFiled: September 24, 2009Date of Patent: December 11, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hitoshi Matsunaga, Kei Kitajima
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Patent number: 8315767Abstract: A control device for an automatic transmission 10 having shift control means 88 operative to select a manual shift mode is provided for preventing acceleration response from deteriorating in the automatic transmission 10. The control device includes automatic up-range control means 90 for switching a range to a āDā range when high oil-temperature determining means determines presence of a high oil-temperature state, and high oil-temperature down-range permitting means 92 for permitting a down-range during a manual shift operation until a selected uppermost gear position GSELECT reaches a determining gear position GJUGE when the accelerator-on drive determining means 86 subsequently determines presence of an accelerator-on drive. Even when obtaining a drive force is attempted during an accelerator-on drive mode after switching the range, the down-range by the manual shift operation is permitted until the selected uppermost gear position GSELECT reaches the determining gear position GJUGE.Type: GrantFiled: June 16, 2009Date of Patent: November 20, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hiroyuki Sawada, Masato Kaigawa, Shinya Toyoda, Kei Kitajima, Yoshio Hasegawa, Fuminori Monji
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Patent number: 8271168Abstract: A shift controller includes: a shift control unit automatically shifting gears of an automatic transmission using a basic shift line map; a shift line map switching control unit switching from the basic shift line map to a high fluid temperature shift line map set on a lower vehicle speed side when a hydraulic fluid temperature in the automatic transmission is higher than a predetermined value; and a low power state determination unit determining whether a vehicle is in a low power state in which a required power related value used for gear shift determination is lower than a predetermined determination value. The shift line map switching control unit switches from the high fluid temperature shift line map back to the basic shift line map when the hydraulic fluid temperature is lower than the predetermined value and the vehicle is in the low power state.Type: GrantFiled: May 18, 2009Date of Patent: September 18, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hiroyuki Sawada, Masato Kaigawa, Kei Kitajima, Yoshio Hasegawa, Fuminori Monji
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Patent number: 8197131Abstract: Until the accuracy in calculation of an estimated oil temperature value which is calculated by means of a heat dissipation amount map reaches a predetermined level, an ECU determines, when a transmission oil temperature well exceeds a predetermined temperature after the engine start, whether or not an oil temperature sensor fails. When it is determined that the oil temperature sensor is normal, the ECU uses the detected oil temperature value to learn about the heat dissipation map. When the accuracy in calculation of the estimated oil temperature value reaches the predetermined level through the learning about the heat dissipation amount map, the ECU determines whether or not the oil temperature sensor fails based on the divergence of the detected oil temperature value relative to the estimated oil temperature value.Type: GrantFiled: July 17, 2009Date of Patent: June 12, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventor: Kei Kitajima
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Publication number: 20110155534Abstract: In a controller of a vehicle drive unit that is one embodiment of the present invention, a plurality of slippage control regions (regions A to C) are set based on the timing of booming noise generation that accompanies engine driving (time from when the vehicle running state enters a region until booming noise is generated) so as to actively use, for example, regions B and C where booming noise is generated if the road load comes to a balance due to a slope or the like and running is then continued and where booming noise is not immediately generated even after the vehicle running state enters the regions, so the frequency of performing lockup slippage control is increased and the fuel saving effects of the lockup slippage control are enhanced.Type: ApplicationFiled: September 24, 2009Publication date: June 30, 2011Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kei Kitajima, Hitoshi Matsunaga
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Publication number: 20110130928Abstract: A shift controller for an automatic transmission capable of automatically shifting up in a manual mode is provided. In the shift controller, a hysteresis between an automatic upshift line and a downshift permission line is set to be smaller as the accelerator opening degree decreases. As a result, when the accelerator opening degree is larger and therefore hunting is more likely to occur, it is possible to avoid an excessively small time interval between a downshift and an upshift. On the other hand, when the accelerator opening degree is smaller and therefore hunting is less likely to occur, a manual downshift permission region can be expanded to a higher rotational speed region, whereby a driver's manual downshift request can be satisfied in a higher vehicle speed region.Type: ApplicationFiled: September 24, 2009Publication date: June 2, 2011Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Hitoshi Matsunaga, Kei Kitajima
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Patent number: 7899593Abstract: Provided are an automatic transmission abnormality diagnosis apparatus and method for an automatic transmission having: a lock-up mechanism; a shift mechanism; and a control mechanism. The automatic transmission is adapted to operate in a slip state, a full lock-up state or a lock-up release state of the lock-up mechanism. The lock-up mechanism is forcibly shifted from the slip state or from the lock-up release state to the full lock-up state in an operation region where the lock-up mechanism is not normally placed in the full lock-up state, and then whether the forcible shift of the lock-up mechanism has been successfully performed is determined. As such, the region for executing the abnormality diagnosis of the hydraulic control mechanism is extended and thus the frequency of the abnormality diagnosis increases, and therefore abnormalities can be promptly detected.Type: GrantFiled: January 28, 2008Date of Patent: March 1, 2011Assignee: Toyota Jidosha Kabushiki KaishaInventors: Masayasu Mizobuchi, Kei Kitajima, Naoyuki Sakamoto
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Publication number: 20100195693Abstract: Until the accuracy in calculation of an estimated oil temperature value which is calculated by means of a heat dissipation amount map reaches a predetermined level, an ECU determines, when a transmission oil temperature well exceeds a predetermined temperature after the engine start, whether or not an oil temperature sensor fails. When it is determined that the oil temperature sensor is normal, the ECU uses the detected oil temperature value to learn about the heat dissipation map. When the accuracy in calculation of the estimated oil temperature value reaches the predetermined level through the learning about the heat dissipation amount map, the ECU determines whether or not the oil temperature sensor fails based on the divergence of the detected oil temperature value relative to the estimated oil temperature value.Type: ApplicationFiled: July 17, 2009Publication date: August 5, 2010Inventor: Kei KITAJIMA
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Publication number: 20100049411Abstract: A downshift allowable vehicle speed is variably set according to a torque converter slippage amount. Specifically, a downshift allowable vehicle speed is variably set by, using a reference downshift allowable vehicle speed when the torque converter slippage amount is 0 and a gear ratio of the automatic transmission after a downshift, calculating an allowable vehicle speed correction amount based on the present torque converter slippage amount and the gear ratio after the downshift, and setting a value obtained by subtracting the allowable vehicle speed correction amount from the reference downshift allowable vehicle speed as the downshift allowable vehicle speed. By such setting, it is possible to set a higher downshift allowable vehicle speed as the torque converter slippage amount becomes smaller, so it is possible to expand a downshift allowable region when the manual gearshift mode is selected.Type: ApplicationFiled: October 29, 2009Publication date: February 25, 2010Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Hitoshi MATSUNAGA, Kei Kitajima
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Publication number: 20100010716Abstract: A control device for an automatic transmission 10 having shift control means 88 operative to select a manual shift mode is provided for preventing acceleration response from deteriorating in the automatic transmission 10. The control device includes automatic up-range control means 90 for switching a range to a āDā range when high oil-temperature determining means determines presence of a high oil-temperature state, and high oil-temperature down-range permitting means 92 for permitting a down-range during a manual shift operation until a selected uppermost gear position GSELECT reaches a determining gear position GJUGE when the accelerator-on drive determining means 86 subsequently determines presence of an accelerator-on drive. Even when obtaining a drive force is attempted during an accelerator-on drive mode after switching the range, the down-range by the manual shift operation is permitted until the selected uppermost gear position GSELECT reaches the determining gear position GJUGE.Type: ApplicationFiled: June 16, 2009Publication date: January 14, 2010Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Hiroyuki SAWADA, Masato Kaigawa, Shinya Toyoda, Kei Kitajima, Yoshio Hasegawa, Fuminori Monji
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Publication number: 20090292430Abstract: A shift controller includes: a shift control unit automatically shifting gears of an automatic transmission using a basic shift line map; a shift line map switching control unit switching from the basic shift line map to a high fluid temperature shift line map set on a lower vehicle speed side when a hydraulic fluid temperature in the automatic transmission is higher than a predetermined value; and a low power state determination unit determining whether a vehicle is in a low power state in which a required power related value used for gear shift determination is lower than a predetermined determination value. The shift line map switching control unit switches from the high fluid temperature shift line map back to the basic shift line map when the hydraulic fluid temperature is lower than the predetermined value and the vehicle is in the low power state.Type: ApplicationFiled: May 18, 2009Publication date: November 26, 2009Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Hiroyuki SAWADA, Masato Kaigawa, Kei Kitajima, Yoshio Hasegawa, Fuminori Monji
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Publication number: 20080183352Abstract: Provided are an automatic transmission abnormality diagnosis apparatus and method for an automatic transmission having: a lock-up mechanism; a shift mechanism; and a control mechanism. The automatic transmission is adapted to operate in a slip state, a full lock-up state or a lock-up release state of the lock-up mechanism. The lock-up mechanism is forcibly shifted from the slip state or from the lock-up release state to the full lock-up state in an operation region where the lock-up mechanism is not normally placed in the full lock-up state, and then whether the forcible shift of the lock-up mechanism has been successfully performed is determined. As such, the region for executing the abnormality diagnosis of the hydraulic control mechanism is extended and thus the frequency of the abnormality diagnosis increases, and therefore abnormalities can be promptly detected.Type: ApplicationFiled: January 28, 2008Publication date: July 31, 2008Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Masayasu MIZOBUCHI, Kei KITAJIMA, Naoyuki SAKAMOTO