Abstract: A method and apparatus for determining oil degradation measures a first electric-current value of a driving current used to operate an electric oil pump at a predetermined consistent revolution, and stores the first electric-current value as an electric-current initial value. Data is corrected by measuring a second electric-current value of the driving current, with the second electric-current value being measured when the electric pump is operated at the predetermined consistent revolution when the engine is driven a predetermined time after the electric-current initial value is stored. The electric-current initial value is compared with the second electric-current value. It is then determined that a viscosity of the oil has become low when a difference between the electric-current initial value and the second electric-current value is equal to or greater than a predetermined value.

Abstract: A twin clutch transmission for reducing the frequency of hit noise occurring in a dog clutch when shifting from neutral to a first speed. The twin clutch transmission includes a plurality of pairs of gears according to the number of speed stages between dual-structured main shafts and a countershaft. A twin clutch is disposed on the main shafts wherein a rotational drive force of an engine is transferred or blocked. A transmission between adjacent speed change gears on each shaft by a dog clutch occurs with a shift drum for switching between an engagement condition of the dog clutch by driving a shift fork. The patterns of guide grooves in the shift drum are formed wherein the dog clutches for a first speed gear and a second speed gear engage simultaneously when the shift drum is rotated by predetermined angles to shift from neutral to the first speed.

Abstract: In a clutch control system for a vehicle having a hydraulic type clutch in the course of power transmission between an engine and a drive wheel the operational response of the clutch is enhanced and the influence of a hysteresis present in oil pressure-stroke characteristic is suppressed. When the clutch is disconnected, a control oil pressure thereof is maintained at a predetermined stand-by oil pressure (allowance compensating oil pressure) P1. At the time of connecting the clutch, the control oil pressure is increased to a predetermined connection oil pressure P2. In bringing the clutch from the connected state into the disconnected state, the control oil pressure is lowered to an oil pressure P3 being below the stand-by oil pressure P1 and being near 0, and is thereafter increased again to the stand-by oil pressure P1.

Abstract: A clutch control system for a transmission for detecting if hydraulic control during shifting is not executed. A first clutch and a second clutch are switched from a disengagement state to an engagement state by receiving a predetermined pressure generated by a hydraulic pump. A transmission executes shifting to an adjacent gear step by operation of switching the engagement state of the first clutch and of the second clutch from one side to the other side. If an elapse time t from the start of clutch switching operation reaches a predetermined time and an input-output speed ratio which is a ratio between engine speed and counter shaft rotational number falls within a predetermined range corresponding to a gear step before shifting, the transmission control unit discontinues the clutch switching operation by stopping the supply of hydraulic pressure to the other side clutch to bring it into the disengagement state.

Abstract: A clutch control system for a twin-clutch type automatic/manual transmission AMT includes a hydraulic pump for driving a first clutch and a second clutch and oil passages for transmitting oil pressures and an AMT control unit for controlling the supply of oil pressures into the oil passages. Upon detection of an engine starting operation, the AMT control unit performs an initial preparatory operation in which the oil pressures are supplied into the oil passages at different timings so as to fill up the oil passages with a working oil, thereby completing the preparations for driving of the clutches. When the oil pressure is supplied into the oil passage after a predetermined oil pressure is generated in the oil passage, the period of time taken for a first speed gear to become usable is shortened, whereby a swift vehicle starting after the starting of the engine can be achieved.

Abstract: A clutch control apparatus for a vehicle provided with a hydraulic clutch in the middle of a power transmission path between an engine and a drive wheel. Before the clutch of the vehicle is brought into an engagement state, intermittent hydraulic pressure Y is applied to the clutch while maintaining the clutch in a disengagement state, and thereafter a predetermined hydraulic pressure is applied to the clutch to bring it into the engagement state. A solenoid valve is provided to control hydraulic pressure supplied to the clutch. Before the clutch is brought into the engagement state, a pulsed drive current D is supplied to the solenoid valve. The clutch control apparatus so configured suppresses a motion delay at the time of engaging the clutch, thereby allowing a quick and smooth start and shifting of the clutch.

Abstract: A hybrid vehicle includes an engine and a drive motor which adds power to power generated by the engine in a superimposed manner to assist the engine. A power control unit includes: a fourth rotor sensor as a vehicle speed sensor which detects vehicle speed of the hybrid vehicle; an accelerator sensor which detects an amount of accelerator operation; and an ECU having an assist map which determines an output command reference value for the drive motor based on the vehicle speed and the amount of accelerator operation. The ECU outputs, to the drive motor, a corrected output command value which is calculated by adding an additional value corresponding to a rate of change in the amount of accelerator operation, to the output command reference value obtained from the assist map.

Abstract: A twin clutch type speed-change apparatus applies a dog clutch to speed-change gears slid on a main shaft and a counter shaft for changing the number of speed-change steps. A twin clutch type speed-change apparatus includes a transmission having a plurality of gear pairs between a main shaft and a countershaft and a twin clutch. The rotational drive force of the engine is connected/disconnected between the transmission and the engine by the twin clutch. A dog clutch with dog teeth and a dog hole is applied between an axially slidably attached slidable gear and an axially non-slidably attached non-slidable gear to select an on gear pair for transmitting the rotational drive gear, from a plurality of gear pairs in the transmission. Rotational drive force is transmitted between the slidable gear slid by a shift fork and the coaxially adjacent non-slidable gear by engagement of the dog clutch.

Abstract: A twin clutch speed-change apparatus that can reduce shift shock includes a transmission with multiple gear pairs disposed between a main shaft and a countershaft. A twin clutch is provided on the main shaft, a rotational drive force from an engine being connected/disconnected between the transmission and the engine, a dog clutch is provided between an axially slidably attached slidable gear and an axially non-slidably attached non-slidable gear to select a gear pair, for transmitting a rotational drive force, from the multiple gear pairs. Dog teeth of the dog clutch include steps different in axial height from each other between a portion abutted against a lateral wall surface of a dog hole when the rotational drive force is transmitted by the dog clutch, and a portion abutted against a lateral wall surface of the dog hole when the rotational drive force is not transmitted by the dog clutch.

Abstract: A twin clutch type speed change control system changes over the gear position by switching between a pair of clutches, to reduce the collision sound generated between a free gear and a slide member at the time of changeover of the gear position. In the twin clutch type speed change control system designed to perform gear position changeovers between odd-ordinal gear positions and even-ordinal gear positions through a process in which an engaged clutch is disengaged whereas a disengaged clutch is engaged, the formerly disengaged clutch is supplied with a minute oil pressure P1 toward the clutch engaging side and is thereby preliminarily moved by a minute amount toward the clutch engaging side, at the time of changeover of the gear position.

Abstract: In an automatic speed change control system for a vehicle wherein a transmission is operated by use of an actuator, to contrive an alleviation of the burden in a shifting operation made by the user after a system starting operation. A shift actuator for controlling the speed change operation of the transmission is provided in a power transmission path. When the transmission is not in a neutral condition at the time when a predetermined system starting operation is conducted, the shift actuator is operated so as to put the transmission into the neutral condition.

Abstract: In a twin clutch type speed change control system in which changeover of gear position is carried out by switching between a pair of clutches, to suppress the noises of clutch being in the disengaged condition during a normal operation with a fixed gear position. In the twin clutch type speed change control system, changeover of gear position between an odd-ordinal gear position and an even-ordinal gear position is effected by disengaging an engaged clutch and engaging a disengaged clutch. During the normal operation with a fixed gear position, the clutch being in the disengaged condition is supplied with a minute oil pressure toward the clutch engaging side, whereby the clutch is moved by a minute amount toward the clutch engaging side.

Abstract: An automatic gear shifting control device of a vehicle can execute an automatic gear shifting control in response to a larger rotational speed. The automatic gear shifting control device includes a gear shifting control instruction part that executes an automatic gear shifting operation of an AMT in response to at least vehicle-speed information. First and second sensors detect rotational speed of front and rear wheels. A rotational-speed-difference detector detects the difference in rotational speed between the front and rear wheels based on information from the first and second sensors. The control part is configured to execute an automatic gear shifting control in response to the vehicle-speed information calculated based on the larger rotational speed out of the rotational speed of the front wheel and the rotational speed of the rear wheel when the difference in rotational speed is detected by the rotational-speed-difference detector.

Abstract: A transmission control device of a motorcycle can detect a predetermined traveling state based on the difference in rotational speed between a front wheel and a rear wheel, and can execute a shift-change control suitable for the traveling state. A transmission control device of a motorcycle includes a shift-change control instruction part that performs an automatic shift change of an AMT (automatic manual transmission) in response to at least vehicle-speed information. A first sensor detects a rotational speed of a front wheel, which constitutes a driven wheel. A second sensor detects a rotational speed of a rear wheel, which constitutes a drive wheel. A rotational-speed-difference detector detects the difference in rotational speed between the front wheel and the rear wheel. The control part inhibits the automatic shift change when the rotational speed of the rear wheel becomes larger than the rotational speed of the front wheel by a predetermined value or more.

Abstract: A motor cooling structure for efficiently cooling a driving motor in a power unit case of the electric vehicle includes a transmission case cover having an air filter mounted on a side surface of a transmission case adjacent to a fan, and a ventilation gap defined between a rear portion of the transmission case cover and the transmission case. The transmission case cover includes a cooling air inlet facing the ventilation gap. When the fan is rotated in synchronism with a crankshaft, an outside cooling air is introduced from the cooling air inlet into the transmission case cover and then passes through the air filter to enter the transmission case, thereby forcibly cooling a transmission. Thereafter, a part of the cooling air is discharged from a central air outlet to the outside of the transmission case, and the remaining cooling air is drawn to the driven portion of the transmission.

Abstract: A performance control system is provided that is adapted to regulate the output of an engine while maintaining stable combustion whereby the perceived operational feel and exhaust efficiency is improved. The performance control system includes an accelerator position sensor for detecting the position of an accelerator by a driver, an electronically controlled throttle adjuster for adjusting the opening of a throttle valve mounted in the intake pipe of an engine with a motor, and a control unit for controlling the throttle adjuster based on the output of the accelerator position sensor. When the engine output, characterized by engine speed or vehicle speed, reaches a predetermined value, the opening of the throttle valve is reduced from the standard opening of the throttle valve, based on the position of the accelerator.

Abstract: A clutch actuation mechanism having a plurality of friction plates engaged with a clutch outer and a clutch inner in a relatively non-rotatable manner and arranged alternately between a bearing plate portion and a pressing plate portion. A clutch disengage/engage control mechanism for switching disengagement/engagement of the clutch actuation mechanism. A clutch piston having opposite sides facing toward a control hydraulic chamber and a hydraulic canceler chamber. A division wall member forming the hydraulic canceler chamber between the division wall member and the clutch piston for forming an oil passage, which introduces lubricating oil toward the friction plates, in cooperation with the clutch inner. A control hydraulic chamber, hydraulic canceler chamber, and division wall member are arranged within a range corresponding to the space between the outer surfaces of a bearing plate portion and pressing plate portion and radially inward of a clutch actuation mechanism.

Abstract: A shift control apparatus for a continuously variable transmission includes a continuously variable transmission for transmitting power of an engine to a driving wheel; a shift actuator for changing a gear ratio of the continuously variable transmission; and a gear ratio controller for controlling the shift actuator such that the gear ratio of the continuously variable transmission exhibits a predetermined shift pattern. The shift controller further includes a battery monitor for detecting remaining charge of a battery charged by a generator connected to the engine, and the shift pattern is changed according to the remaining charge of the battery. The shift control apparatus ensures an operating feel similar to that during ordinary running regardless of remaining charge of a battery. A method of controlling a continuously variable transmission in a vehicle is also disclosed.

Abstract: A centrifugal fan is mounted to an inner plate of a centrifugal clutch as a heat-generating rotating device, and an intake port of a casing is formed near a front side in the axial direction of the centrifugal fan. The centrifugal fan includes a base plate connected to the inner plate of the centrifugal clutch, plural fins formed on the base plate, blow-off holes each formed between arbitrary adjacent fins and extending axially through the base plate, and guide walls for guiding a radially outward air flow over the base plate into the blow-off holes. Air just after admitted from the intake port passes through the blow-off holes and is blown against the centrifugal clutch.

Abstract: To provide a power module driving control apparatus and a hybrid vehicle capable of obtaining sufficient accelerator response despite adoption of a speed sensing type clutch for connection and disconnection of a power drive between an engine side and a driving wheel side. When a rotational speed on an input side of a centrifugal clutch falls short of a set value, at which the clutch can be connected, and an acceleration request is made by a rider, a control unit controls a motor generator so as to bring the rotational speed on the input side of the clutch near to the set value. When the motor generator is made to function as a motor, rotation on the input side of the clutch is assisted. When the motor generator functions as a generator, an amount of electricity generated is decreased.