Continuously Variable Friction Transmission Patents (Class 477/37)
  • Patent number: 6839617
    Abstract: Operating range of feedback in CVT ratio control has been extended by use of stabilized values as an actual value of CVT ratio. The actual value of CVT ratio is derived from first and second pulse train signals provided by input and output speed sensors. Updating of rotational speed of the input member is repeated at intervals governed by the first pulse train. Updating of rotational speed of the output member is repeated at intervals governed by the second pulse train. Updating of an old value of a ratio between the latest value of the rotational speed of the input member and the latest value of the rotational speed of the output member to a new value thereof is repeated each time immediately after the rotational speeds of the input and output members have been updated since the latest updating of an old value of the ratio.
    Type: Grant
    Filed: April 10, 2003
    Date of Patent: January 4, 2005
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Michel Mensler, Shinichiro Joe, Taketoshi Kawabe
  • Publication number: 20040254047
    Abstract: Systems and methods for efficiently and effectively controlling the rate of change of ratio, not simply the ratio, in a CVT. By controlling the rate of change of ratio, the acceleration or deceleration of a vehicle can be controlled in an efficient manner. Furthermore, the rate of change of ratio can be controlled by controlling the clamping pressure of the pulleys and/or differential pressure between the pulleys with minimal slip by using a servo control mechanism adapted for control by a system controller based on equilibrium mapping and other control parameters.
    Type: Application
    Filed: March 19, 2004
    Publication date: December 16, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Andrew A. Frank, Thomas Dreumont
  • Patent number: 6830533
    Abstract: A control apparatus for controlling transmission ratio of a toroidal-type continuously variable transmission unit of a continuously variable transmission apparatus, the continuously variable transmission apparatus has: a toroidal-type continuously variable transmission unit, which changes a transmission ratio between pair of disks by shifting trunnions in the axial direction of pivot shafts by using actuators; and, a differential unit of a gear type including a combination of a plurality of gears, the control apparatus having: rotation speed control unit; transmission ratio setting unit; oil pressure measuring unit; and, transmission ratio correcting unit operating in response to a deviation of a pressure difference between a measured value by the oil pressure measuring unit and a target value of a torque passing through the toroidal-type continuously variable transmission unit, and adjusting the transmission ratio of the toroidal-type continuously variable transmission unit so as to eliminate the deviation.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: December 14, 2004
    Assignee: NSK Ltd.
    Inventors: Eiji Inoue, Takashi Imanishi, Toshiro Toyoda
  • Patent number: 6802796
    Abstract: A control device is provided in a hybrid-driven auxiliary system using an engine and a motor as driving force. The control device includes: an auxiliary unit into which the motor is integrally assembled; current controlling means for controlling an electric current of the motor for driving or generating; current detecting means for detecting the electric current of the motor; and load torque computing means for computing, based on the electric current of the motor, a load torque when the auxiliary unit is operated.
    Type: Grant
    Filed: June 20, 2003
    Date of Patent: October 12, 2004
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Hironori Asa, Yasushi Suzuki, Keiichi Uno
  • Publication number: 20040171457
    Abstract: A hydraulic control circuit is disclosed for a continuously variable transmission having a continuously variable transmission unit (“variator”) in which the position of at least one ratio determining element (e.g. A roller 28 of a toroidal race rolling traction type variator) is influenced by means of a hydraulic actuator (100, 100′, 100″). The control circuit comprises a flow line (106) through which hydraulic fluid is fed to and from the actuator means (eg. A control valve 116 disposed in the flow line) for adjusting pressure in the flow line, and a first valve (125) connected to the flow line so that opening of the first valve diverts flow of fluid to/from the flow line.
    Type: Application
    Filed: December 3, 2003
    Publication date: September 2, 2004
    Inventor: John William Edward Fuller
  • Patent number: 6766237
    Abstract: A shift control system for a toroidal CVT employs a shift technique for setting a torque shift compensation quantity so as to be increased as an actual gear ratio approaches a low-speed side gear ratio region including a lowest-speed gear ratio and so as to be decreased when the actual gear ratio is in the low-speed side gear ratio region. Further, the shift control system is arranged to select a gear ratio in a low-speed side gear ratio region after a gear ratio in a high-speed side gear ratio region is selected.
    Type: Grant
    Filed: December 24, 2002
    Date of Patent: July 20, 2004
    Assignee: JATCO LTD
    Inventors: Masaki Watanabe, Yasutaka Kawamura, Hiroyasu Tanaka, Masaoki Horio
  • Publication number: 20040128048
    Abstract: In a controller of a vehicle transmission, the transmission includes a continuously variable transmission 3 and a planetary gear mechanism 4 and is coupled to an output of an engine 1. The transmission includes a first shift mode using only the continuously variable transmission 3 and a second shift mode using in combination the continuously variable transmission 3 and the planetary gear mechanism 4.
    Type: Application
    Filed: August 28, 2003
    Publication date: July 1, 2004
    Inventors: Kunihiro Iwatuki, Hiroyuki Shioiri
  • Patent number: 6757603
    Abstract: In a slippage prevention apparatus of a belt-drive continuously variable transmission for an automotive vehicle in which a transmission ratio is controlled by a speed-change hydraulic pressure brought closer to a desired speed-change hydraulic pressure, a quick-acceleration-frequency decision section is provided to determine whether a frequency of quick accelerating operations is low or high. Also provided is a desired hydraulic pressure decision section that sets the desired speed-change hydraulic pressure used during an operating mode that the frequency of quick accelerating operations is low to a relatively lower pressure level than the desired speed-change hydraulic pressure used during an operating mode that the frequency of quick accelerating operations is high.
    Type: Grant
    Filed: January 8, 2003
    Date of Patent: June 29, 2004
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Mikio Nozaki
  • Patent number: 6726594
    Abstract: A control system for a vehicle in which an internal combustion engine whose output torque is controlled based on a required output power is coupled to a continuously variable transmission whose input rotation speed is controlled based on the required output power. A controller of the system determines a final target operating point of the engine which is defined by the output torque and the input rotation speed, on the basis of the required output power, and sets a transient operating point to one of possible operating points that can be achieved within a predetermined period of time such that the operating point of the engine approaches the final target operating point. The controller then controls the output torque and the input rotation speed of the continuously variable transmission so as to operate the engine at the set transient operating point.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: April 27, 2004
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Makoto Mizuno, Kazuhisa Mogi
  • Publication number: 20040054458
    Abstract: A method and apparatus for regulating the transmission ratio of a continuously variable transmission. A set point value for adjusting the transmission ratio can be changed as a function of the operating parameters of a power train that includes the transmission. The set point value is composed of an initial control value and a regulating value. The initial control value depends on at least two operating parameters of the transmission. The set point value is updated to take into account changes that occur during operation of the transmission.
    Type: Application
    Filed: July 23, 2003
    Publication date: March 18, 2004
    Inventors: Michael Reuschel, Thomas Pfund, Thomas Endler
  • Publication number: 20040053741
    Abstract: A drive arrangement of a motor vehicle, which comprises a motor and a stepless automatic transmission for the driving of drive wheels, is typically operated in a normal operating mode in connection with normal driving operation and in a brake engagement operating mode in connection with a slip of at least one of the drive wheels that exceeds a certain value. During the brake engagement operating mode, strong fluctuations of the transmission's transmission ratio can arise, or the case can arise, that the motor vehicle drives with a low motor torque but a high drive rotational speed. This is perceived as uncomfortable by the driver. The new method shall increase the driving comfort.
    Type: Application
    Filed: July 22, 2003
    Publication date: March 18, 2004
    Inventors: Oswin Roeder, Horst Wild
  • Publication number: 20040018912
    Abstract: The invention concerns a method and a drive arrangement for controlling an internal combustion engine, said internal combustion engine acting via a variable transmission, particularly a continuously variable transmission, on drivable wheels or the like of a motor vehicle, in which a fuel feed to the internal combustion engine is at least reduced in dependence on an operating state and the internal combustion engine operates in overrun mode and a gear ratio of the transmission is adjusted, independently of driver intention, in dependence on at last one operating parameter of the motor vehicle.
    Type: Application
    Filed: March 13, 2003
    Publication date: January 29, 2004
    Inventors: Bernhard Mencher, Klaus Ries-Mueller, Joachim Luh
  • Publication number: 20040014557
    Abstract: An electronic transmission control system is provided that can achieve a transmission ratio based on the operator inputs and the current vehicle operating conditions. The transmission constantly connects the engine to the load, and the transmission ratio is only varied by a change in command from the present invention. The transmission's mechanical function is solely to vary the ratio between its input and output. In using the present invention, an operator must select an operating mode, either automatic or manual, using a two-position switch. While in the automatic mode, the present invention determines the vehicle speed by considering the position of the throttle and the operator's use of brakes. In the manual mode, the present invention further considers the operator's selection of a gear condition.
    Type: Application
    Filed: May 12, 2003
    Publication date: January 22, 2004
    Applicant: Sauer-Danfoss Inc.
    Inventors: Ryan R. Carlson, Manfred Maiers, Steven H. Gluck
  • Patent number: 6679808
    Abstract: A starting shift control system for a continuously variable transmission is provided which includes a control unit having a high start judgment device for judging whether or not a high start in a high speed side gear ratio is caused on the basis of a comparison between the generated number of the input rotation pulses and the generated number of the output rotation pulses from the time a first vehicle starting operation is performed after start of a prime mover, and a high start control device for restricting downshifting from the high speed side gear ratio to a target gear ratio when a start of the vehicle is judged to be the high start. A starting shift control method is also provided.
    Type: Grant
    Filed: September 18, 2001
    Date of Patent: January 20, 2004
    Assignee: Jatco LTD
    Inventors: Hiroyasu Tanaka, Shigeki Shimanaka, Junya Takayama, Satoshi Takizawa, Masato Koga, Takayuki Suzuki, Takashi Hara
  • Patent number: 6671601
    Abstract: A decision is made as to whether a vehicle is traveling in an uphill traveling mode or in a downhill traveling mode with reference to an incremental running resistance &Dgr;R determined on the basis of a running resistance that will act on the vehicle while the vehicle is traveling in a flat road traveling mode. A desired traction Fd for a full-open throttle state in which a throttle valve is fully open is set if the vehicle is in the uphill traveling mode by using the incremental running resistance &Dgr;R, and a desired traction Fd for a full-closed throttle state in which the throttle valve is fully closed is set if the vehicle is in the downhill traveling mode by using the incremental running resistance &Dgr;R. The desired traction Fd and an achieved traction F(t) in the full-open throttle state at a present traveling speed V are compared if the vehicle is in the uphill traveling mode.
    Type: Grant
    Filed: December 16, 1998
    Date of Patent: December 30, 2003
    Assignee: Fuji Jukogyo Kabushiki Kaisha
    Inventor: Yuuki Abiru
  • Publication number: 20030229437
    Abstract: A toroidal continuously-variable transmission shift control apparatus includes a controlling section to control an actual transmission ratio toward a target transmission ratio by producing a control command in one of a forward traveling control mode for a forward vehicle traveling state, and a reverse traveling control mode; and a control modifying section arranged to select one of the forward traveling control mode and the reverse traveling control mode in accordance with a first parameter representing a driver's intention. The control modifying section is configured to detect a change of the vehicle traveling direction in accordance with a second parameter which is the actual transmission ratio, and to modify the shift control of the toroidal continuously-variable transmission so as to shift the actual transmission ratio to a speed decreasing side upon detection of the change of the vehicle traveling direction.
    Type: Application
    Filed: May 13, 2003
    Publication date: December 11, 2003
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Shinichiro Joe, Taketoshi Kawabe
  • Patent number: 6659906
    Abstract: In a toroidal continuously variable transmission, a secondary oil pump is provided in addition to a primary oil pump driven by an engine. The secondary oil pump is driven in response to rotation of a road wheel. A hydraulic servo mechanism is connected to a trunnion to create an offset of the power roller from a neutral position for a tilting motion of the power roller. A feedback device is provided for feeding a degree of progress for ratio changing back to the hydraulic servo mechanism so that the power roller returns to the neutral position when a desired transmission ratio has been reached. When the road wheel is rotated in a stopped state of the engine, hydraulic pressure from the secondary oil pump is supplied to the hydraulic servo mechanism so that an actual transmission ratio is brought closer to a desired transmission ratio.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: December 9, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Toshikazu Oshidari
  • Patent number: 6656084
    Abstract: A control apparatus for feedback-controlling an engaging action of a clutch disposed between an engine and a transmission of an automotive vehicle, wherein an engaging force control device is operated upon an engaging action of the clutch, for determining a control amount and feedback-controlling the engaging action on the basis of the determined control amount such that the clutch is placed in a desired state of engagement, and a control amount limiting device is operated to limit the determined control amount when the determined control amount has changed to cause an engaging force of the clutch to be reduced.
    Type: Grant
    Filed: April 16, 2001
    Date of Patent: December 2, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Daisuke Inoue, Hideki Yasue, Katsumi Kono, Tadashi Tamura, Hiroji Taniguchi, Kenji Matsuo
  • Publication number: 20030216216
    Abstract: A control apparatus for controlling transmission ratio of a toroidal-type continuously variable transmission unit of a continuously variable transmission apparatus, the continuously variable transmission apparatus has: a toroidal-type continuously variable transmission unit, which changes a transmission ratio between pair of disks by shifting trunnions in the axial direction of pivot shafts by using actuators; and, a differential unit of a gear type including a combination of a plurality of gears, the control apparatus having: rotation speed control unit; transmission ratio setting unit; oil pressure measuring unit; and, transmission ratio correcting unit operating in response to a deviation of a pressure difference between a measured value by the oil pressure measuring unit and a target value of a torque passing through the toroidal-type continuously variable transmission unit, and adjusting the transmission ratio of the toroidal-type continuously variable transmission unit so as to eliminate the deviation.
    Type: Application
    Filed: April 18, 2003
    Publication date: November 20, 2003
    Applicant: NSK Ltd.
    Inventors: Eiji Inoue, Takashi Imanishi, Toshiro Toyoda
  • Patent number: 6645120
    Abstract: A speed change control valve (7) houses a spool (8) of comprising a land (83) which can face a supply port (7P) supplying an oil pressure, and lands (84, 85) which can respectively face a pair of drain ports (7D, 7D) formed on either side of the supply port (7P). Output ports (7L, 7H) which allow a first and second oil chamber of an hydraulic cylinder to communicate selectively with the supply port (7P) or the drain ports (7D) according to the displacement of a spool (8), are provided in the speed change control valve (7). In the neutral position of the spool (8), the lands (84, 85) respectively face the drain ports (7D), a width L1 of the land (83) is set to be equal to or greater than a width L1 of the supply port (7P), and a width L3 of the lands (84, 85) is set to a width at which the drain port (7D) can open.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: November 11, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Motoharu Nishio, Toshikazu Oshidari, Jun Sugihara
  • Patent number: 6641502
    Abstract: A control device for a gear of a motor vehicle, where the control device adjusts the speeds or transmissions of a gear according to a control program. In order to improve the setting of options and parameters to influence the control program, it is proposed that a memory be provided in the control device in which the options or parameters to influence the control program are filed in an alterable manner. An input device is connected with the memory and that input device can access the memory in a writing fashion. It is thus possible to set or alter options or parameters to influence the control program via the input device.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: November 4, 2003
    Assignee: Dr. Ing. h.c.F. Porsche AG
    Inventor: Udo Heim
  • Publication number: 20030195688
    Abstract: Operating range of feedback in CVT ratio control has been extended by use of stabilized values as an actual value of CVT ratio. The actual value of CVT ratio is derived from first and second pulse train signals provided by input and output speed sensors. Updating of rotational speed of the input member is repeated at intervals governed by the first pulse train. Updating of rotational speed of the output member is repeated at intervals governed by the second pulse train. Updating of an old value of a ratio between the latest value of the rotational speed of the input member and the latest value of the rotational speed of the output member to a new value thereof is repeated each time immediately after the rotational speeds of the input and output members have been updated since the latest updating of an old value of the ratio.
    Type: Application
    Filed: April 10, 2003
    Publication date: October 16, 2003
    Applicant: NISSAN MOTOR CO.,LTD.
    Inventors: Michel Mensler, Shinichiro Joe, Taketoshi Kawabe
  • Publication number: 20030176256
    Abstract: The technique of the invention sets a relationship between the throttle opening (corresponding to the accelerator opening), the vehicle speed, and the target torque of a drive shaft, so as to enable a greater braking torque to be output in a working status of a cruise control system than a braking torque, which is output to the drive shaft in a full closed position of the accelerator opening in a non-working status of the cruise control system. This arrangement ensures output of a sufficient braking force to the drive shaft even under the condition of a relatively large drive load applied to the drive shaft, for example, during a downslope run, thus enabling the vehicle speed to be certainly kept at a preset level under the control of the cruise control system.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 18, 2003
    Inventors: Kensuke Kamichi, Hidehiro Oba
  • Patent number: 6622075
    Abstract: A method and apparatus for regulating the transmission ratio of a continuously variable transmission. A set point value for adjusting the transmission ratio can be changed as a function of the operating parameters of a power train that includes the transmission. The set point value is composed of an initial control value and a regulating value. The initial control value depends on at least two operating parameters of the transmission. The set point value is updated to take into account changes that occur during operation of the transmission.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: September 16, 2003
    Assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG
    Inventors: Michael Reuschel, Thomas Pfund, Thomas Endler
  • Patent number: 6612964
    Abstract: In a method of controlling a transmission ratio of a continuously variable toroidal transmission, a holding force for an intermediate roller is pilot-controlled as a function of the torques acting on the toroidal disks and of the pivoted position of the intermediate roller, and/or the adjustment path of the intermediate roller is fed back statically or dynamically into a control circuit.
    Type: Grant
    Filed: February 8, 2001
    Date of Patent: September 2, 2003
    Assignee: Siemens Aktiengesellschaft
    Inventors: Joachim Bamberger, Joachim Horn, Peter Michau
  • Patent number: 6612965
    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: Grant
    Filed: March 12, 2001
    Date of Patent: September 2, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Masayuki Yasuoka, Hiromasa Sakai
  • Patent number: 6605016
    Abstract: A hydraulic type pressing device secures the contact pressure between the peripheral surfaces of respective power rollers and the inner surfaces of respective input side disks and respective output side disks. When a torque to be transmitted changes abruptly, the pressing force of the pressing device is set to a value corresponding to the maximum torque to be transmitted by a toroidal type continuously variable transmission. According to this configuration, the variation of the transmission ratio based on the variation of the elastic deformation values at the respective portions is suppressed to prevent the uncomfortable feeling of a driver.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: August 12, 2003
    Assignee: NSK Ltd.
    Inventors: Shinji Miyata, Daping Liu
  • Patent number: 6602163
    Abstract: When the temperature of operating fluid of an actuator is low, a target input rotation speed lower limit value (NinL) is set. The lower limit value (NinL) is greater than a lower limit value set for a normal temperature of operating fluid. A target input rotation speed (Nint) is calculated from the state of running of a vehicle, such as the amount of operation of an accelerator, the vehicle speed, etc. If the target input rotation speed is lower than the lower limit value (NinL), the target input rotation speed is reset to the lower limit value (NinL). As a result of a control that includes the above-described steps, the speed ratio &ggr; becomes relatively high before the vehicle stops. Therefore, even if the speed ratio-changing rate is low, the speed ratio (&ggr;) can be brought to or near a maximum value (&ggr;max) before the vehicle stops. Thus, reductions in the speed ratio-changing rate caused by low temperature of the operating fluid of the actuator can be curbed.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: August 5, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tadashi Tamura, Hideki Yasue, Katsumi Kono, Daisuke Inoue, Yoshiaki Yamamoto, Hiroki Kondo, Hiroji Taniguchi, Kenji Matsuo, Yuji Hattori
  • Patent number: 6604039
    Abstract: The trunnion (23) of a vehicle toroidal continuously variable transmission is displaced by a step motor (52) via a control valve (56) and oil pressure servo cylinder (50) in order to vary a speed ratio of the transmission. A controller (80) calculates a target value (z*) of a control variable (z) based on an accelerator pedal depression amount (APS) and output disk rotation speed (&ohgr;co) (S5). Further, a time-variant coefficient (f) showing the relation between the trunnion displacement (y) and variation rate ({dot over (&phgr;)}) of the gyration angle (&phgr;) of the power roller, is calculated (S10). The error between the speed change response of the transmission and a target linear characteristic can be decreased by determining a command value (u) to the step motor (52) under a control gain determined based on a time differential ({dot over (f)}) of the coefficient (f) (S20).
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: August 5, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Shinichiro Joe, Taketoshi Kawabe, Itsuro Muramoto
  • Patent number: 6599220
    Abstract: A controller (80) calculates a target speed ratio of a continuously variable transmission (2) incorporated into an infinitely variable transmission for a vehicle and a target vehicle acceleration based on a vehicle running state. When a predetermined creep torque control condition holds (S90-S93, S101), the controller (80) corrects the target speed ratio such that the deviation of the target acceleration from the real vehicle acceleration to decrease. By controlling the speed ratio of the continuously variable transmission to the corrected target speed ratio, the infinitely variable transmission generates a creep torque consistent with the driver's intention.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: July 29, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Yasushi Narita, Yoshinori Iwasaki, Tatsuya Nagato
  • Publication number: 20030135316
    Abstract: A shift control system of a toroidal CVT for a vehicle is arranged to calculate a command gear ratio by adding a desired gear ratio and a torque shift compensation quantity for compensating a difference between the desired gear ratio and an actual gear ratio which difference is generated by a shifting operation of the toroidal CVT, and to set a magnitude of the torque shift compensation quantity employed in an automatic shift range to be larger than a magnitude of the torque shift compensation quantity employed in other shift range except for the automatic shift range when the actual gear ratio is in a first gear ratio region except for a second gear ratio region including a largest gear ratio.
    Type: Application
    Filed: December 24, 2002
    Publication date: July 17, 2003
    Applicant: JATCO Ltd
    Inventors: Yasutaka Kawamura, Shigeki Shimanaka, Masaki Watanabe
  • Publication number: 20030135315
    Abstract: A shift control system for a toroidal CVT employs a shift technique for setting a torque shift compensation quantity so as to be increased as an actual gear ratio approaches a low-speed side gear ratio region including a lowest-speed gear ratio and so as to be decreased when the actual gear ratio is in the low-speed side gear ratio region. Further, the shift control system is arranged to select a gear ratio in a low-speed side gear ratio region after a gear ratio in a high-speed side gear ratio region is selected.
    Type: Application
    Filed: December 24, 2002
    Publication date: July 17, 2003
    Applicant: JATCO Ltd.
    Inventors: Masaki Watanabe, Yasutaka Kawamura, Hiroyasu Tanaka, Masaoki Horio
  • Patent number: 6575871
    Abstract: The invention relates to an arrangement and a method for controlling an adjusting speed for a change of an actual transmission ratio into a steady-state desired transmission ratio (shifting operation) for a continuously variable transmission mounted in the drive train of a motor vehicle. In the arrangement of the invention, it is provided that the shifting operation is subdivided into individual periods (dT) of fixed duration. During each period (dT), a dynamic desired transmission ratio (udyn) is determined by multiplying the steady-state desired transmission ratio (ustat) by a gradient (udot). The change of the actual transmission ratio (u) into a dynamic desired transmission ratio (udyn) of each period (dT) takes place with a constant adjusting speed (vu).
    Type: Grant
    Filed: January 2, 2001
    Date of Patent: June 10, 2003
    Assignee: Robert Bosch GmbH
    Inventors: Juergen Loeffler, Martin-Peter Bolz, Karl-Heinz Senger, Holger Huelser
  • Patent number: 6575874
    Abstract: A working vehicle for work such as a turf grass management is provided, which has an improved climb-up performance and an improved engine-break force at a stage of climbing down a slope. The working vehicle mounts a working machine driven by an engine and also a continuously variable transmission thereon, and has a climb-up or climb-down mode Df which sets a transmission ratio of the continuously variable transmission at a maximum value during travel of a slope. The climb-up or climb-down mode Df is selected by an operation of a shift lever or automatically detected by climb-up or climb-down detectors. When the mode Df is set, a pulley ratio of the continuously variable transmission is controlled so as to have the maximum transmission ratio based on a command signal of a control unit.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: June 10, 2003
    Assignee: Fuji Jukogyo Kabushiki Kaisha
    Inventors: Hiroyuki Ono, Yasuhiko Miyamoto
  • Publication number: 20030105572
    Abstract: A system for enhanced ratio control in a continuously variable transmission (CVT) includes a ratio control element positionable by an actuator in response to an actuator command to establish various CVT ratios in the CVT. At least one sensor generates a train of pulses indicative of speed of rotation of a predetermined rotary member of the CVT. A measured CVT ratio generator derives information of an actual CVT ratio out of at least the train of pulses to give a measured value of CVT ratio. A filter processes the measured value of CVT ratio in a manner to refine the information of the actual CVT ratio to give an estimated value of CVT ratio. A command generator determines the actuator command such that the actuator command remains unaltered when a deviation of the estimated value of CVT ratio from a desired value of CVT ratio stays within a dead zone.
    Type: Application
    Filed: December 4, 2002
    Publication date: June 5, 2003
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Shinichiro Joe, Taketoshi Kawabe, Michel Mensler
  • Patent number: 6569051
    Abstract: An infinite Speed ratio continuously variable transmission comprises a power recirculation mode clutch (9) and direct mode clutch (10). At least one of the power recirculation mode clutch (9) and direct mode clutch (10) comprises an electromagnetic two-way clutch. The electromagnetic two-way clutch maintains the engaged state during excitation and can transmit drive force from both the drive side and non-drive side. On the other hand, when there is a change-over from the energized state to the non-energized state, a one-way clutch state is obtained wherein drive force is permitted only in the transmission direction of drive force in the instant of the change-over to non-excitation. When a drive force is input in the reverse direction to the drive force transmitted in the one-way clutch state, the one-way clutch state is disengaged, and the disengaged state of the clutch is maintained until subsequent re-excitation.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: May 27, 2003
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hiroyuki Hirano, Kazuhiro Yamada, Yasushi Narita, Tatsuya Nagato, Hiromasa Sakai, Motoharu Nishio, Hiroaki Kuramoto, Hirofumi Shimizu, Masaki Nakano, Eio Sagara, Masayoshi Kimura
  • Patent number: 6565480
    Abstract: A control apparatus for a drive system, in which a power source is activated to output a torque by an energy fed from an energy source so that the torque is transmitted to rotary members through a torque transmission element having a variable transmission torque capacity. The stop of the power source due to the exhaustion of energy is predicted to increase the transmission torque capacity of the torque transmission element.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: May 20, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiroatsu Endo, Tatsuya Ozeki, Yukio Kinugasa, Kazumi Hoshiya
  • Patent number: 6546910
    Abstract: A method and apparatus controls an internal combustion engine having electromagnetically driven valves. A target cylinder torque required of one of a plurality of cylinders is individually calculated in accordance with a target engine torque, and a timing for opening and closing each of a plurality of intake and exhaust valves in each of the plurality of cylinders is determined in accordance with the target cylinder torque. Thereby the torque of the internal combustion engine is individually controlled for each of the plurality of cylinders.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: April 15, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masaaki Tanaka, Yasushi Ito, Shoji Katsumata, Keiji Yoeda, Hideyuki Nishida, Makoto Ogiso, Isao Matsumoto
  • Patent number: 6547691
    Abstract: A shift control system for a continuously variable transmission has a target gear ratio corresponding value calculating device for calculating a target gear ratio corresponding value of the continuously variable transmission according to at least a throttle opening, a shift control device for controlling a gear ratio of the continuously variable transmission so that the target gear ratio corresponding value can be obtained. It further has a reactive force applying device disposed on an accelerator pedal and applying a reactive force, which increases according to an increase of the accelerator pedal opening, to a pedal depression force of a driver in a large accelerator pedal opening range.
    Type: Grant
    Filed: August 2, 2001
    Date of Patent: April 15, 2003
    Assignee: Jatco Transtechnology Ltd.
    Inventor: Akira Hino
  • Patent number: 6549838
    Abstract: A control strategy and method for controlling friction element engagement and disengagement time for an automatic transmission when the transmission is operating at cold ambient temperatures. During drive-to-reverse or reverse-to-drive friction element engagements with power on, the strategy compensates for a tendency of an oncoming friction element to gain capacity before an off-going clutch loses capacity, thereby avoiding a potential friction element tie-up condition when the transmission is operated with intermediate or high levels of engine torque as the friction elements are sequentially engaged and disengaged during cold rock cycling.
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: April 15, 2003
    Assignee: Ford Global Technologies, Inc.
    Inventors: Brian Michael O'Neil, John Paul Gorys, John Mathew Pogorzelski, Jacob Martin Povirk, Joseph Scott Slayton, Steven DeWayne Dunn
  • Patent number: 6522965
    Abstract: A method for setting a multiplication of a continuously variable automatic transmission (CVT transmission) comprises the following steps: a) it is determined in a test module (M1, M1′) whether an operating situation is present in which a program module (M2, M2′) for adapting an existing transmission multiplication (i_v_ist) to a vehicle speed (v_F) or to an output rotational speed (n_ab) of the transmission is activated; in the negative a transmission specified multiplication (i_v_stratagy, i_v_start) is determined as new transmission specified multiplication (i_v_soll) from a characteristic field for a regular driving strategy; b) it is tested in the program module (M2, M2′) whether the vehicle speed (v_F) or the output rotational speed (n_ab) of the transmission is higher than a predetermined limiting value (v_F_limit, n_ab_limit); c) in the case of a positive inquiry, a predefined transmission specified multiplication (i_v_ABS, i_start_w) assigned to the determined operating state is s
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: February 18, 2003
    Assignee: ZF Freidrichshafen AG
    Inventor: Armin Gierling
  • Patent number: 6519522
    Abstract: The invention relates to a method for determining a starting gear step for a vehicle with a stepped variable speed transmission with several gear steps. It is proposed that a maximum admissible value for a slip time (12) and/or a maximum admissible value for a frictional work (14) of the starting clutch during the starting process, the same as an available engine torque (10) for starting be determined, that beginning with a highest suitable gear step (18) for starting, values for the slip time (20) and/or the frictional work (22) be calculated in advance depending on the vehicle mass (8), that the precalculated values (20, 22) be compared with the maximum admissible values (12, 14), that the calculation loop be repeated with the next smaller suitable gear step for starting when at least one of the precalculated values is greater than the maximum admissible values and that a gear step be issued as starting gear step when the precalculated values are smaller than or equal to the maximum admissible values.
    Type: Grant
    Filed: February 15, 2001
    Date of Patent: February 11, 2003
    Assignee: ZF Friedrichshafen AG
    Inventors: Andreas Wolf, Matthias Winkel, Christoph Rüchardt, Bertram Wengert, Jürgen Müller
  • Patent number: 6497636
    Abstract: In a method and apparatus for controlling a driving engine/transmission unit having a continuously variable automatic transmission, the transmission output torque acting upon the driving wheels of a vehicle and the engine reaction torque retroacting upon the driving engine can be adjusted by way of a regulated transmission variable.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: December 24, 2002
    Assignee: Bayerische Motoren Werke Aktiengesellshaft
    Inventors: Thomas Schleicher, Thomas Kress, Lothar Wolf
  • Publication number: 20020173403
    Abstract: A speed change control method of controlling a speed change ratio of a continuously variable transmission mechanism including a traction continuously variable transmission, includes: estimating a tilt angle of a power roller included in the continuously variable transmission based on an input rotating speed and an output rotating speed of the continuously-variable transmission mechanism;
    Type: Application
    Filed: April 15, 2002
    Publication date: November 21, 2002
    Applicant: KAWASAKI JUKOGYO KABUSHIKI KAISHA
    Inventors: Yukinobu Kohno, Masaaki Uenishi, Kenichi Nakashima, Tatsuhiko Goi, Koji Kawakami
  • Patent number: 6478712
    Abstract: An alarm is emitted when a vehicle attempts to start when the speed ratio of a toroidal continuously variable transmission is small. A sensor (63. 67. 73) detects that the speed ratio is smaller than a predetermined range. A microprocessor (61) controls an alarm (68) to operate when an ignition switch (66) is in a position for starting an engine, while the speed ratio is smaller than the predetermined range.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: November 12, 2002
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Yasutaka Kawamura, Masato Koga, Masatoshi Akanuma, Mitsuru Watanabe, Satoshi Takizawa, Shigeki Shimanaka, Hiroyasu Tanaka, Junya Takayama
  • Publication number: 20020165063
    Abstract: A control apparatus is provided for a vehicle including an internal combustion engine and a continuously variable transmission capable of controlling an output speed of the engine. A controller of the control apparatus determines a first operating point at which a total fuel consumption amount is minimized as an optimal operating point, such that the total fuel consumption amount is obtained by adding an amount of a fuel consumed by an exhaust purifying device disposed in an exhaust system to an amount of a fuel consumed by the engine for generating a required output. The controller then controls an engine load and also controls a speed ratio of the transmission so that the engine operates at the optimal operating point.
    Type: Application
    Filed: March 8, 2002
    Publication date: November 7, 2002
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Yasushi Ito
  • Publication number: 20020161503
    Abstract: Enhanced ratio control in a toroidal drive of a T-CVT is provided. A factor of proportionality is computed by which a trunnion axial displacement and a T-CVT ratio rate are related. A filter in the form of a characteristic equation is established. This filter includes a physical quantity indicative of the T-CVT ratio and a physical quantity indicated by an actuator command, as inputs, a quasi-state quantity, as a state quantity, and a transition coefficient for the quasi-state quantity. The transition coefficient includes an observer gain. The quasi-state quantity is computed using the filter. An estimated quantity of a system state quantity of the T-CVT is computed using the quasi-state quantity, the observer gain, and a trunnion angular position. The system state quantity includes at least the first physical quantity. The observer gain is corrected in response to the factor of proportionality to keep the transition coefficient unaltered.
    Type: Application
    Filed: February 5, 2002
    Publication date: October 31, 2002
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Shinichiro Joe, Taketoshi Kawabe
  • Publication number: 20020132697
    Abstract: A method for controlling a continuously variable transmission that includes a multi-stage torque sensor. At least on e switchover point from one stage to another stage is determined based upon a given input load and is correlated with transmission operating parameters, such as transmission ratio, hydraulic pressure within a chamber in the torque sensor, and transmission output torque.
    Type: Application
    Filed: February 28, 2002
    Publication date: September 19, 2002
    Inventors: Michael Reuschel, Anton Fritzer
  • Publication number: 20020128115
    Abstract: A controller (80) calculates a target speed ratio of a continuously variable transmission (2) incorporated into an infinitely variable transmission for a vehicle and a target vehicle acceleration based on a vehicle running state. When a predetermined creep torque control condition holds (S90-S93, S101), the controller (80) corrects the target speed ratio such that the deviation of the target acceleration from the real vehicle acceleration to decrease. By controlling the speed ratio of the continuously variable transmission to the corrected target speed ratio, the infinitely variable transmission generates a creep torque consistent with the driver's intention.
    Type: Application
    Filed: March 5, 2002
    Publication date: September 12, 2002
    Applicant: NISSAN MOTOR CO., LTD.,
    Inventors: Yasushi Narita, Yoshinori Iwasaki, Tatsuya Nagato
  • Patent number: 6440037
    Abstract: A control system for a vehicle including a continuously variable is constructed: such that a target output of a prime mover for achieving a target driving force is determined on the basis of the target driving force; such that a target output speed is determined on the basis of the target output; such that a gear ratio of the continuously variable transmission is controlled so that an output speed of the prime mover may be the target output speed; such that a target output torque of the prime mover for achieving the target driving force is determined on the basis of the target driving force; and such that a load of the prime mover is controlled on the basis of the target output torque. The control system further comprises a corrector for correcting a control quantity to control the load of the prime mover so that the output torque of the prime mover may have the sum of the target output torque and an output torque for keeping the idle run of the prime mover.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: August 27, 2002
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Isao Takagi, Hirofumi Kubota