Patents by Inventor Hiromasa Sakai

Hiromasa Sakai 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).

  • Publication number: 20020028722
    Abstract: In an infinitely variable transmission, a continuously variable transmission (2) outputs the rotation of an input shaft (1) at an arbitrary speed ratio, and a fixed speed ratio transmission (3) outputs the rotation of the input shaft (1) at a fixed speed ratio. A planetary gear set (5) varies the rotation direction and speed of the output shaft (6) according to the difference of the output rotation speed of the fixed speed ratio transmission (2) and the output rotation speed of the continuously variable transmission (2). A sensor (81) which detects the rotation speed of the input shaft (1) and a sensor (82) which detects the output rotation speed of the continuously variable transmission (2) are provided, and a microprocessor (80) precisely calculates the rotation direction and rotation speed of the output shaft (6) from these rotation speeds.
    Type: Application
    Filed: June 25, 2001
    Publication date: March 7, 2002
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Hiromasa Sakai, Motoharu Nishio, Hiroaki Kuramoto, Shinichiro Joe
  • Patent number: 6351700
    Abstract: An infinite speed ratio continuously variable transmission is provided with a continuously variable transmission (2), fixed speed ratio transmission (3), planetary gear set (5), power recirculation clutch (9) and direct clutch (10). A target speed ratio of the infinite speed ratio continuously variable transmission is set based on a vehicle speed and an accelerator pedal depression amount. When the target speed ratio varies beyond a rotation synchronous point, a control unit (80) assigns an order of priority to control of the power recirculation clutch (9) and direct clutch (10), and control of the speed ratio of the continuously variable transmission (2), and thereby causes a real speed ratio of the infinite speed ratio continuously variable transmission to vary in the same direction until it reaches the target speed ratio (S21, S22, S31, S32, S121, S122).
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: February 26, 2002
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Itsuro Muramoto, Taketoshi Kawabe, Shin-ichiro Joe, Yasushi Narita, Hiromasa Sakai, Motoharu Nishio
  • Publication number: 20010041640
    Abstract: A three-way clutch unit (9) comprising a forward clutch (91), second clutch (92) and forward one way clutch (93) which sets a power recirculation mode, a high clutch (10) which sets a direct mode, and a mode change-over valve (175) which supplies an oil pressure to one of the high clutch (10) and second clutch (92), are provided.
    Type: Application
    Filed: March 30, 2001
    Publication date: November 15, 2001
    Inventors: Hiromasa Sakai, Toshikazu Oshidari
  • Publication number: 20010041644
    Abstract: When an engine control unit (70) controls an engine rotation speed Ne to an idle rotation speed, and a select range is changed over from a non-travel range to a travel range, a speed change control unit (80) commands an increase of engine torque supplied to the engine control unit (70), and increases the transmission torque of a continuously variable transmission (2) according to the increase amount of the engine torque.
    Type: Application
    Filed: March 12, 2001
    Publication date: November 15, 2001
    Inventors: Masayuki Yasuoka, Hiromasa Sakai
  • Patent number: 6317672
    Abstract: In an infinite speed ratio transmission comprising a continuously variable transmission (2), reduction gear unit (3) and planetary gear set (5), the speed ratio of the continuously variable transmission (2) is controlled by a step motor (36). A range selected by a selector lever (86) is detected by a sensor (84). When the selected range has changed from a stationary range to one of a forward motion range and a reverse motion range, a microprocessor (80) first drives the step motor (36) to a predetermined position (S48, S54).
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: November 13, 2001
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiroaki Kuramoto, Motoharu Nishio, Hiromasa Sakai, Yasushi Narita, Tatsuya Nagato, Manzaburou Abe
  • Patent number: 6312357
    Abstract: A creep torque is controlled in a non-finite speed ratio transmission device, wherein a planetary gear unit (5) varies a rotation direction of a final output shaft (6) according to a relative rotation of a toroidal continuously variable transmission (2) and fixed speed ratio transmission (3). The controller comprises a hydraulic cylinder (39) which varies the speed ratio of the toroidal continuously variable transmission (2) by driving a trunnion (23), a shift control valve (46) which supplies a hydraulic pressure to the hydraulic cylinder (30) according to a displacement position, a step motor (36) which displaces the shift control valve (46) according to a command signal, and a mechanical feedback member (35, 37, 38) which feeds back the speed ratio of the toroidal continuously variable transmission (2) to the shift control valve (46).
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: November 6, 2001
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Motoharu Nishio, Hiroaki Kuramoto
  • Patent number: 6287232
    Abstract: In a non-finite speed ratio transmission device using a toroidal continuously variable transmission (2), a hydraulic cylinder (30) for driving a power roller (20) via a trunnion (23), a shift control valve (46) for controlling a supply direction of oil to an oil chambers (30A, 30B) of the hydraulic cylinder (30), and a precess cam (35) which feeds back a displacement of the power roller (20) to the shift control valve (46) so as to shut-off the flow of oil to and from the oil chambers (30A, 30B), are provided. The shift control valve (46) comprises a drain port (46J) which can be connected to the oil chamber (30A) and a drain port (46I) which can be connected to the oil chamber (30B).
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: September 11, 2001
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Motoharu Nishio
  • Patent number: 6142906
    Abstract: A toroidal continuously variable transmission (11) having power rollers (18A-18D) held between input discs (19, 20) and output discs (21, 22) and transmitting power and a torque converter (12) having a lock up clutch (12D) connected to the continuously variable transmission (11) are provided. The line pressure of a working fluid supplied from a pump (1) is adjusted by a pressure regulator valve (2), and the adjusted line pressure is introduced to a lock up control valve (5) for controlling a fluid pressure to be supplied to the lock up clutch (12D) of the torque converter (12) through a pressure passage (31). Further, an oil cooler (32) is interposed in a downstream portion of the lock up control valve (5).
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: November 7, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Jun Sugihara
  • Patent number: 6086505
    Abstract: A pivotal feedback line has at one end thereof a follower member that is slidably put on a work surface of a precess cam actuated by a trunnion of a toroidal type continuously variable transmission. A speed control valve has a spool. The spool is moved for feeding a hydraulic actuator of the transmission with a hydraulic pressure to control the trunnion. An electric actuator has an output member. A speed change link is arranged to which the other end of the pivotal feedback link, the spool of the speed control valve and the output member of the electric actuator are connected through first, second and third articulated members respectively.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: July 11, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Hiromasa Sakai
  • Patent number: 6080079
    Abstract: First oil chambers (80A) which drive a toroidal continuously variable transmission in a speed ratio decrease direction are connected to a first port (82B) of an oil pressure control valve (62) via a first passage (86A). Second oil chambers (80B) which drive the toroidal continuously variable transmission in a speed ratio increase direction are connected to a second port (82C) via a second passage (86B). The oil pressure control valve (62) selectively connects a pump port (82A, 82F, 82G) and a drain pot (82D, 82E, 82H) to the first and second ports (82B, 82C) according to the displacement of a spool (84). A damper (96, 98, 102, 108, 109, 114, 116, 120) is connected to one of the ports so as to exert a damping action on the oil passing through the oil pressure control valve (62).
    Type: Grant
    Filed: July 26, 1999
    Date of Patent: June 27, 2000
    Assignee: Nissan Motor Co., Ltd
    Inventor: Hiromasa Sakai
  • Patent number: 6056094
    Abstract: A hydraulic control device controls hydraulic fluid for shifting an automatic transmission by a pressure control valve, and supplies operating hydraulic fluid diverted from the pressure control valve via a torque converter pressure passage to a lock up clutch of the torque converter. A lubrication passage which lubricates the automatic transmission is connected via an orifice to a torque converter pressure passage, and the pressure in this torque converter pressure passage is limited by a regulator valve to a predetermined upper limit value. Further, there is included a bypass valve which directly supplies hydraulic fluid from the torque converter pressure passage via the orifice to the lubrication passage when the pressure in the torque converter pressure passage rises above a predetermined pressure.
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: May 2, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Hiromasa Sakai
  • Patent number: 6045480
    Abstract: A toroidal continuously variable transmission (11) having power rollers (18A-18D) held between input discs (19, 29) and output discs (21, 22) and transmitting power and a torque converter (12) having a lock up clutch (12D) connected to the continuously variable transmission (11) are provided. The line pressure of a working fluid supplied from a pump (1) is adjusted by a pressure regulator valve (2), and the adjusted line pressure is introduced to a lock up control valve (5) for controlling a fluid pressure to be supplied to the lock up clutch (12D) of the torque converter (12) through a pressure passage (31). Further, an oil cooler (32) is interposed in a downstream portion of the lock up control valve (5).
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: April 4, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Jun Sugihara
  • Patent number: 6023648
    Abstract: An anti-creep control apparatus has a forward clutch control section that controls the hydraulic pressure of a forward clutch so as to slip the forward clutch when an automatic transmission is set in a drive range and the vehicle is stopped. The anti-creep control apparatus sets a target engagement time that is inversely proportional to the engine rotation speed at the time just before starting anti-creep control. The anti-creep control apparatus controls an oil pressure modulator so that one of a slip amount of the forward clutch and the output shaft rotation speed of the torque converter becomes nearly zero when the target engagement time elapses.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: February 8, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Takashi Murasugi, Motoharu Nishio, Hiromasa Sakai
  • Patent number: 5950787
    Abstract: A rotation clutch device rotates on an axis of an automatic transmission. The rotation clutch device comprises a clutch piston which slides around the axis of the automatic transmission for the engagement of the clutch device. First and second chamber are formed to slide the clutch piston in the direction of the engagement by receiving hydraulic pressure respectively. A cancel chamber is formed opposite to the first and second chambers through the clutch piston to cancel the centrifugal pressure generated in the first and second chambers. A selector valve selectively supplies hydraulic pressure to the first and second chambers according to a selected shift position of the automatic transmission to adapt to a different required engagement capacity in each shift position.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: September 14, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Takashi Murasugi, Hiromasa Sakai, Motoharu Nishio
  • Patent number: 5938563
    Abstract: A shift control apparatus of an automatic transmission executes a transient control of an engagement pressure of a first speed selecting friction element when a first speed is selected after a higher speed is once selected during a change from a neutral range to a forward drive range. A band brake pressure for selecting the second speed is rapidly increased at a first moment. A forward clutch pressure for selecting the first speed is increased at a second moment delaying to the first moment by a predetermined period adjusted to a line pressure lowered period. The forward clutch pressure is pre-charged during a period between the first and second moments, then being hold for a preset time period at a return spring corresponding pressure adjusted by a leaning control, and being increased by a slope adjusted by the leaning control for a predetermined period to establish the second speed by the engagement of the forward clutch.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: August 17, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Motoharu Nishio, Takashi Murasugi, Hiromasa Sakai
  • Patent number: 5935039
    Abstract: The same rotation torque is input to a continuously variable transmission of a vehicle which continuously varies a speed change ratio and a reduction gear unit. A planetary gear mechanism is provided comprising an output shaft which varies a rotation direction according to a relation between the output speed of the continuously variable transmission and the output speed of the reduction gear unit. The continuously variable transmission varies the speed change ratio according to an oil pressure balance between two oil chambers. A direction change-over valve selectively supplies a first oil pressure and a second oil pressure to these oil chambers, and a control valve controls a differential pressure of the first oil pressure and second oil pressure.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: August 10, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Motoharu Nishio
  • Patent number: 5928111
    Abstract: A fuel cut-off and fuel-supply recovery control system for an internal combustion engine coupled to an automatic power transmission with a lock-up torque converter having a lock-up device operable at either one of an open converter state and a locked-up state through a lock-up control based on engine and vehicle operating conditions, comprises an electronic control module configured to store a fuel-cut engine speed (N.sub.1, N.sub.3) above which a fuel cut-off control is executed under a specified engine and vehicle operating condition and a fuel-supply recovery engine speed (N.sub.2) below which a fuel-supply recovery control is restarted so that fuel supply to the engine is recovered from the fuel cut-off control. The electronic control module variably determines a hysteresis between the fuel-cut engine speed and the fuel-supply recovery engine speed so that a deviation (N.sub.3 -N.sub.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: July 27, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Satoshi Sakakibara, Hiromasa Sakai
  • Patent number: 5925086
    Abstract: In apparatus and method for controlling a gear shift of a vehicular automatic transmission, the automatic transmission the automatic transmission having a releasing frictional element, a clutching frictional element, and a source of a releasing working liquid pressure to be applied to the releasing frictional element and a clutching working liquid pressure to be applied to the clutching frictional element, a gear shift in the automatic transmission being carried out by a shift from the releasing frictional element to the clutching frictional element, during a time duration from a time at which a gear shift instruction is outputted to a time at which a torque phase is started, the releasing working liquid pressure is reduced and reached without undershooting to a first predetermined working liquid pressure value under which the releasing frictional element is in a state immediately before an occurrence of a slip and the clutching working liquid pressure is set at least a second predetermined working liquid pre
    Type: Grant
    Filed: August 12, 1997
    Date of Patent: July 20, 1999
    Assignee: Nissan Motor Co., Ltd
    Inventors: Hiromasa Sakai, Motoharu Nishio, Takashi Murasugi
  • Patent number: 5916058
    Abstract: An anti-creep control apparatus of an automatic transmission has a forward clutch control section which controls the hydraulic pressure of a forward clutch by slipping the forward clutch when the automatic transmission is set in a drive range and the vehicle is stopped while an engine is operating. The anti-creep control apparatus controls an hydraulic pressure of the forward clutch to be held or increased by a predetermined value when a relative rotation of the forward clutch is detected during the anti-creep control. The controlled hydraulic pressure is set as a lower limit value of the forward clutch hydraulic pressure in a present anti-creep control.
    Type: Grant
    Filed: July 22, 1997
    Date of Patent: June 29, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiromasa Sakai, Takashi Murasugi, Motoharu Nishio
  • Patent number: 5906556
    Abstract: A line pressure control apparatus of an automatic transmission controls the line pressure of the automatic transmission under a lockup condition to ensure an engagement capacity and an amount of lubrication oil for an engaged friction element under a high vehicle speed condition. The line pressure control apparatus comprises a line pressure lowering section, a vehicle speed deciding section and a pressure changing section. The pressure lowering section lowers a line pressure under a lockup condition of the automatic transmission. The vehicle speed deciding section decides whether a vehicle speed of the automotive vehicle is higher than a predetermined value. The pressure changing section changes the line pressure under the lockup condition from the lowered line pressure to a line pressure under a normal condition when the vehicle speed is higher than the predetermined value.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: May 25, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Chiaki Harada, Hiromasa Sakai, Kazuhiro Takatori