Abstract: A lubricating device for an internal combustion engine includes an oil tank chamber defined by being separated from a crank chamber by a partition wall that is formed between a crankcase and a crankcase cover of the internal combustion engine. Oil pumped by a scavenge pump is supplied to a tank supply port which is open at an upper portion of the oil tank chamber to the oil tank chamber. The oil stored in the oil tank chamber is sucked from a feed suction port which is open at a lower portion of the oil tank chamber to be supplied to respective regions for lubrication of the internal combustion engine by a feed pump. An oil passage penetrating inside the oil tank chamber is formed below the tank supply port at an upper portion of the oil tank chamber.

Abstract: A shift controller for a motor vehicle includes an electric motor configured to rotate a shift drum associated with a transmission. An oil temperature sensor is configured to detect temperature of lubricating oil for the transmission. A controller is configured to control the electric motor. The controller controls the electric motor to operate in a preset first motor duty until a first predetermined time elapses after operation of the electric motor is started when the shift drum is turned from a first predetermined position to a second predetermined position. The controller is also configured to operate the electric motor in a second motor duty calculated based upon oil temperature after the first predetermined time elapses.

Abstract: A shift controller with a first clutch CL1 that connects/disconnects the torque to a first main shaft and a second clutch CL2 connects/disconnects the torque to a second main shaft. A transmission is configured so that dog clutches DC1, DC2 for first speed and for second speed are engaged in a predetermined turned position P1-2 of a shift drum. A linear solenoid valve that supplies clutch oil pressure, a shift solenoid that switches a destination of the supply oil pressure between both clutches and a controller that controls the supply oil pressure and the turning of the shift drum are provided. The controller supplies predetermined oil pressure P1 to the CL2 in neutral, switches the destination of supply oil pressure to the CL1 when the shift drum is turned to P1-2 according to a shift instruction to engage gears and supplies maximum oil pressure P3 to the CL1 in predetermined time ta.

Abstract: A transmission includes a first shifting part and a second shifting part which shift power of an internal combustion engine, a first shift clutch transmitting and interrupting the power to the first shifting part, and a second shift clutch transmitting and interrupting the power to the second shifting part, and a selection mechanism which selects gear steps. The selection mechanism includes three shifters that are respectively guided by cam grooves of a single shift drum through shift forks. The shifters can be respectively moved to selection positions where the gear steps are selected and to neutral positions where the gear steps are not selected in the first shifting part and the second shifting part. The cam grooves guide the shifters to the selection positions in each of the first shifting part and the second shifting part for each of predetermined rotational positions of the shift drum.

Abstract: In a clutch device wherein a plurality of clutch plates are relatively non-rotatably engaged with a clutch outer, a plurality of clutch disks disposed alternately with the clutch plates are relatively non-rotatably engaged with a clutch inner, and an end plate disposed so that the clutch plates and the clutch disks are disposed between itself and a piston slidably fitted in the clutch outer is relatively non-rotatably and axially movably supported on the clutch outer in the manner of being restricted in movement toward one end side in the axial direction, to prevent the clutch inner from coming out of position at the time of assembling the clutch device into position, thereby to enhance workability in the assembling operation, and to prevent the clutch inner from generating a collision sound by colliding against other member than the component members of the clutch device when the clutch is disengaged.

Abstract: An internal combustion engine with a torque converter for extending the temperature range of a hydraulic fluid allowing the function of the torque converter toward lower temperatures. A crankshaft is formed with an oil passage extending there along, an inlet hole for supplying a hydraulic fluid to the torque converter and an outlet hole for discharging the hydraulic fluid. The crankshaft includes a shaft bearing for supporting a rotating shaft for the torque converter. The inlet hole is provided at an axial end of the shaft bearing and contacts the shaft bearing. Flow resistance due to the shaft bearing can be greatly reduced to thereby allow a smooth supply of the hydraulic fluid into the torque converter. When the temperature of the hydraulic fluid is low and the viscosity of the hydraulic fluid is high, a quantity of oil at a certain pressure can be supplied to the torque converter.

Abstract: A transmission assembly includes a shift drum operable to rotate in first and second directions. The shift drum includes a common speed change position, where both a fastest forward gear and a reverse gear are capable of becoming engaged, in such a manner that a reverse stopper arm fits at a first end of a reverse cam groove formed on the shift drum. When the shift drum is rotated in the second rotation direction, opposite to the first direction, from a state where the reverse gear is engaged, the reverse stopper arm surmounts the outer periphery of the shift drum from the first end of the reverse cam groove, without requiring the application of an external force thereto, so as to become detached and to move towards a second end of the reverse cam groove.

Abstract: A vehicular transmission has a structure which enables a reverse idle gear to absorb and reduce excessive back torque inputted from drive wheels. At the time of reverse traveling motion, a counter shaft and a reverse gear are connected to each other through the intermediation of a clutch mechanism, whereby the power of the counter shaft is transmitted from the reverse gear, a driven gear, a hollow shaft, and a drive gear to the drive shaft by way of a final gear. When a large back torque is inputted to the final gear from the drive shaft, the inputted back torque is transmitted to the drive gear, and is then further transmitted to the driven gear by way of the hollow shaft. Since the hollow shaft is thin-walled and has reduced rigidity, it undergoes circumferential twisting due to the back torque inputted, whereby the back torque is reduced.

Abstract: A vehicle transmission includes first and second main shafts that enable switching of power transmission from an engine; a counter shaft connected to a drive wheel; and gear trains with a plurality of shift stages provided between each of the first and second main shafts and the counter shaft. The vehicle transmission also includes shifters which switch between engagement with and disengagement from a gear constituting part of each of the gear trains so as to switch the established states of the gear trains, and to prevent, during running at the most frequently used shift stage, the occurrence of gear rattle produced by a gear train other than the gear train with such a shift stage. With this configuration, in the running state of using a particular gear train with the highest frequency of the established states among the gear trains, the gear trains, excluding the particular gear train, are in the non-established state.

Abstract: An automatic transmission assembly having a transmission unit including a plurality of gear pairs, a shift drum, a pair of clutches; and a controller. The controller performs a preliminary upshifting action in advance for angularly moving the shift drum depending on a next gear position in an upshifting direction while rotary drive power is being maintained at a given gear position, and when an upshifting command is output, the controller engages one of the clutches simultaneously with the command. When a downshifting command is output, the controller performs a preliminary downshifting action in advance based on the downshifting command. The partially neutral positions are provided between predetermined angular positions on the shift drum for temporarily reducing the angular speed of the shift drum when the shift drum is being angularly rotated.

Abstract: A transmission for a vehicle in which changing a shift position is achieved by sliding a shifter. In sliding the shifter to change the established condition of gear trains respectively corresponding to a plurality of shift positions, the transmission of power from an engine to a main shaft is cut off. A feed mechanism for sliding the shifter is configured to reduce the sliding speed of the shifter or to once stop the sliding operation of the shifter in a neutral condition during the sliding operation of the shifter in changing the established condition of the gear trains. The resulting configuration reduces the engagement noise when changing the shift position.

Abstract: A lubricating device for an internal combustion engine includes an oil tank chamber defined by being separated from a crank chamber by a partition wall that is formed between a crankcase and a crankcase cover of the internal combustion engine. Oil pumped by a scavenge pump is supplied to a tank supply port which is open at an upper portion of the oil tank chamber to the oil tank chamber. The oil stored in the oil tank chamber is sucked from a feed suction port which is open at a lower portion of the oil tank chamber to be supplied to respective regions for lubrication of the internal combustion engine by a feed pump. An oil passage penetrating inside the oil tank chamber is formed below the tank supply port at an upper portion of the oil tank chamber.

Abstract: A vehicular transmission includes a shift drum center with a plurality of gear train establishment notches disposed, equally spaced apart from each other, on the outer periphery thereof. The gear train establishment notches establish a specific gear train selected from among a plurality of gear trains by selectively engaging a drum stopper arm therein. The shift drum center further includes half neutral notches to be engaged with the drum stopper arm. The half neutral notches are disposed on the outer periphery of the shift drum center and at a central portion between each pair of the gear train establishment notches, respectively. The resulting configuration effectively suppresses an engagement noise during changing of a gear position through a sliding motion of a shifter.

Abstract: A vehicular transmission for an internal combustion engine includes lead grooves disposed on an outer periphery of a shift drum have communication portions connecting a pair of gear train establishment portions extending circumferentially along the shift drum. The communication portions include half neutral portions formed at a center thereof, extending circumferentially along the shift drum. The resulting configuration suppresses an engagement noise to a minimum during changing of a gear position through a sliding motion of a shifter.

Abstract: A transmission for a vehicle is provided which prevents generation of a speed change shock at the time of starting the vehicle from a neutral condition. In the transmission, hydraulic clutches are each put into a connected state according to an action of an oil pressure, and a plurality of selectively engageable speed-stage gear trains are provided so that a neutral condition can be obtained. At the time of shifting from the neutral condition, where the oil pressures in hydraulic clutches are in a lowered state, to a starting condition in which a starting gear train is engaged, pressure in the hydraulic clutch corresponding to the starting gear train is controlled by a control valve, so that the oil pressure in the hydraulic clutch is maintained in the lowered state during and immediately after a shifting operation, and is subsequently increased in response to complete engagement of the starting gear train.

Abstract: A gear transmission permits an increased flexibility in the layout of shift gears and reduces the axial size of the transmission by providing an engaging portion on a specific one of the shift gears. The gear transmission includes a main shaft having drive gears, a countershaft having driven gears adapted to be respectively driven by the drive gears to set predetermined shift positions, and shifters engageable with specific gears of the drive gears and the driven gears. The specific gears respectively have engaging portions for engaging the shifters, whereby the main shaft rotationally drives the countershaft through any one of the shifters and any one of the specific gears at any one of the predetermined shift positions. Of the engaging portions, the outer diameter of the engaging portion is larger than the outer diameter of a toothed portion of the drive gear as one of the specific gears.

Abstract: In the transmissions of the background art, two larger-diameter gears are mounted on a final shaft thereby causing an increase in weight of the transmission. The present invention reduces the weight of a transmission by mounting only one larger-diameter gear on a final shaft.

Abstract: A transmission includes a first shifting part and a second shifting part which shift power of an internal combustion engine, a first shift clutch transmitting and interrupting the power to the first shifting part, and a second shift clutch transmitting and interrupting the power to the second shifting part, and a selection mechanism which selects gear steps. The selection mechanism includes three shifters that are respectively guided by cam grooves of a single shift drum through shift forks. The shifters can be respectively moved to selection positions where the gear steps are selected and to neutral positions where the gear steps are not selected in the first shifting part and the second shifting part. The cam grooves guide the shifters to the selection positions in each of the first shifting part and the second shifting part for each of predetermined rotational positions of the shift drum.

Abstract: A transmission M of a vehicular power transmission system has a first shifting part and a second shifting part which shift a power of an internal combustion engine, a first shift clutch transmitting and interrupting the power to the first shifting part, and a second shift clutch transmitting and interrupting the power to the second shifting part. A start clutch transmitting and interrupting the power to the first shift clutch and the second shift clutch is constructed of a centrifugal clutch C having a clutch shoe. The resulting configuration provides a vehicular power transmission system which has excellent efficiency of power transmission and durability, as well as being capable of being manufactured at low cost, and being capable of relieving a start shock.

Abstract: Supplying fluids different in pressure from one end of a revolving shaft without providing a diagonal hole in the revolving shaft for supply holes for feeding hydraulic fluid and lubricating oil. The time for manufacturing and the cost of providing a hydraulic fluid feeder to the revolving shaft is reduced. A hydraulic fluid feeder includes a central hole provided on the centerline of the revolving shaft. Hollow tubes having a smaller outside diameter than the inside diameter of the central hole are concentrically inserted into the central hole and the central hole is partitioned. Either of the passages formed by partitioning functions as a hydraulic fluid supply passage for the hydraulic equipment and the other functions as a hydraulic fluid supply passage for another piece of hydraulic equipment or a lubricating oil supply passage for a bearing provided on the revolving shaft.