2897 results about "Gear ratio" patented technology

An engine system and method are disclosed for controlling pre-ignition of an alcohol fuel. In one embodiment, the fuel injection timing is adjusted to cause the fuel to avoid combustion chamber surfaces. In another embodiment, the fuel injection timing is adjusted to spray the fuel directly onto the piston surface to cool the piston. Also disclosed is a cylinder cleaning cycle in which engine knock is purposely caused for one to hundreds of engine cycles by adjusting the fuel content away from alcohol toward gasoline. Further measures to cause knock which are disclosed: adjusting spark timing, intake boost, exhaust gas fraction in the cylinder, cam timing, and transmission gear ratio.

A clutch mechanism is disclosed for use with a hybrid electric vehicle wherein the electric motor-generator and engine are arranged in a series configuration. The clutch mechanism is positioned between and in communication with the electric motor-generator and engine to allow for either direct drive or a predetermined gear ratio between the electric motor-generator and engine. The electric motor-generator is preferably an integrated electric motor and generator. The engine is preferably a combustion engine.

Power roller-side concave grooves are opposed to disk-side concave grooves 19, 19 so as to have angles therebetween in a rolling contact area between a peripheral surface of the power roller and a one-side surface 17 of a disk 16 in an axial direction regardless of a transmission gear ratio of a toroidal continuously variable transmission. Accordingly, the disk-side concave grooves 19, 19 are formed so as to have angles with respect to a circumferential direction of the disk 16 when viewed from a normal direction relative to the one-side surface 17 in the axial direction. Meanwhile, the power roller-side concave grooves are formed into a concentric shape (or a spiral shape) about a central shaft of the power roller. As a result, it is possible to prevent a decrease of a contact area in the rolling contact area regardless of the transmission gear ratio.

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In general, a firing control unit determines working chamber firings during operation of the engine that are suitable for delivering a desired engine output. In one aspect, the firing control unit is arranged to isolate the generation of firing sequences having frequency components in a frequency range of concern and to alter the firing sequence in a manner that reduces the occurrence of frequency components in the frequency range of concern. In another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. In preferred embodiments, the frequency characteristics of the filter are variable. In various embodiments, the frequency characteristics of the filter vary as a function engine speed and/or a transmission gear ratio.

PCT No. PCT/JP97/03887 Sec. 371 Date Jun. 25, 1998 Sec. 102(e) Date Jun. 25, 1998 PCT Filed Oct. 27, 1997 PCT Pub. No. WO98/19083 PCT Pub. Date May 7, 1998There is disclosed a vehicle control system that controls an automatic transmission by utilizing road information stored in a navigation system unit. In response to the road information stored in a data memory, the upper-limit of a shiftable gear ratio range is determined, thereby allowing change of the gear ratio only within the restricted range. The actual downshift is carried out in response to initiation of a decelerating operation by the driver, such as release of the accelerator pedal, which prevents unnecessary upshift and provides favorable transmission control in conformity with the driver's intention.

An automatic transmission is capable of obtaining appropriate gear ratios for six forward shifts and one reverse shift. The automatic transmission includes a first planetary gear, a second planetary gear, a planetary gear unit including a third planetary gear, and a fourth planetary gear. Also provided are first, second, third and fourth shaft elements, first and second first clutch elements, first, second, and third brake elements, the first clutch element is capable of selectively interconnecting the input shaft and the fourth shaft element. The second clutch element is capable of selectively interconnecting the input shaft and the carrier of the single planetary gear. The first brake element is capable of selectively fixing the first shaft element. The second brake element is capable of selectively fixing the second shaft element. The third brake element is capable of selectively fixing either the sun gear or the carrier of the double pinion planetary gear.

A powertrain system is provided that includes a prime mover and a change-gear transmission having an input, at least two gear ratios, and an output. The powertrain system also includes a power shunt configured to route power applied to the transmission by one of the input and the output to the other one of the input and the output. A transmission system and a method for facilitating shifting of a transmission system are also provided.

A closed loop shift control apparatus and method based on estimated torque in friction elements controls a torque transfer phase when shifting from a low gear configuration to a high gear configuration for an automatic transmission system. When pressure actuated friction elements are selectively engaged and released to establish torque flow paths in the transmission, estimates of torsional load exerted on the off-going friction element are used to predict the optimal off-going friction element release timing for achieving a consistent shift feel. The estimated torque is preferably calculated by using estimated torque signals generated as a function of speed measurements represented either the engine speed and turbine output speed or transmission output speed and wheel speed under dynamically changing conditions.

RET antenna with motor and clutch assembly that is operative to mechanically disengage the DC motor and drive unit (also called the gear-motor unit) from the phase shifter adjustment shaft during a manual tilt operation. Disengaging the gear-motor unit removes the drag of the motor and the high gear ratio gear box from the phase shifter control rod making it easier to manually turn the phase shifter control knob. In addition, the clutch disengages the gear-motor without disengaging the position detector from the phase shifter control rod so that position calibration is not lost during manual tilt adjustment. When the manual tilt operation is completed, the mechanical tilt clutch enables the gear-motor unit to be reliably re-engaged with the phase shifter control rod for motorized electrical tilt operation without having to re-calibrate the position detector.

Methods and systems are provided for controlling a vehicle engine coupled to a stepped-gear-ratio transmission. One example method comprises, in response to a first vehicle moving condition, shutting down the engine and at least partially disengaging the transmission while the vehicle is moving; and during a subsequent restart, while the vehicle is moving, starting the engine using starter motor assistance and adjusting a degree of engagement of a transmission clutch to adjust a torque transmitted to a wheel of the vehicle.

A first rotor (24; 124) and a second rotor (25; 125) are arranged in a coaxial and mutually rotatable relationship and are provided with a first driven gear (41; 141) and a second driven gear (42; 142), respectively. A drive shaft (31; 131) is also provided with a first drive gear (43; 143) and a second drive gear (44; 144) which are commonly connected to an output shaft of an electric motor (32; 132), and mesh with the first and second driven gears, respectively, at slightly different gear ratios. The first and second rotors are connected via a thread feed mechanism (36; 136) that converts a relative rotation between the first and second rotors into an axial linear movement between the first and second rotors that is used for changing a distance between a vehicle body part and a corresponding end of a suspension spring in a vehicle height adjusting system (9; 109). Owing to a differential rotation of a high gear ratio between the first and second rotors, a significant torque amplification is possible with a compact arrangement. The use of spur gears instead of a worm gear mechanism minimizes torque loss.

A vehicle transmission includes a differential gear set having five coaxial gear elements and an output member. Two of the gear elements are controllable via torque transmitting mechanisms such as electric motors to establish a plurality of speed ratios between the input shaft and the output shaft. Two of the other gear elements are selectively operatively connectable to an output shaft via a gear arrangement that allows for a plurality of speed ratios between the gear elements and the output shaft. Additional torque transmitting mechanisms such as clutches are selectively engageable to provide continuously variable speed ranges between the input shaft and the output shaft, fixed gear ratios and an electric drive mode. The various speed ratios enable a plurality of compound split operating modes as well as an input split mode.

A speed change system for work vehicle having a continuously variable transmission device selects a first change gear ratio which is set larger than a smallest change gear ratio, when an engine rotational speed is a first set rotational speed which is set equal or close to an idling rotational speed of an engine; retains the change gear ratio of the continuously variable transmission device at the smallest change gear ratio, when the engine rotational speed is equal to or above a second set rotational speed set on a high-speed side relative to the first set rotational speed; and makes the change gear ratio of the continuously variable transmission device larger between the first change gear ratio and the smallest change gear ratio, as the engine rotational speed at that moment becomes lower, when the engine rotational speed is between the first and second set rotational speeds.