Abstract: The present invention relates to a shifting device for a transmission unit of a vehicle, in particular a vehicle that is driven by muscle force. The transmission unit has a first shaft, which is formed as a hollow shaft, on which a plurality of free gears is mounted. The free gears are in engagement with a corresponding plurality of gearwheels, which are mounted on a second shaft, wherein the free gears are connectable to the first shaft by means of selecting devices. The selecting devices can be actuated by means of a camshaft arranged coaxially in the first shaft, wherein the camshaft is connected to a driving device in order to be rotated relative to the first shaft to actuate the selecting means.

Abstract: A shift mechanism that provides a shift mechanism for enabling smooth gear shifting by a transmission, and a vehicle equipped therewith. With this mechanism, a shift drum, to which shift forks are connected via grooves on an outer periphery, is held every predetermined rotation angle. When differences are produced in the degree of rotation between a third rotating member that rotates by motor rotation and a second rotating member that rotates in accordance with the third rotating member, bias is accumulated in a torsion spring. Bias that is accumulated is released when the rotation angle of the third rotating member equals or exceeds a predetermined angle of rotation, rotating a first rotating member via a second rotating member, and rotating the shift drum quickly.

Abstract: A vehicle transmission comprises a locking mechanism selectively preventing an at least one shift drum disposed on a shift drum shaft from rotating. The locking mechanism is movable between a first position and a second position. When in the first position, the locking mechanism prevents the at least one shift drum from rotating in the first direction to engage a first locked position. When in the second position, the locking mechanism prevents the at least one shift drum from rotating in the second direction to engage a second locked position. The second locked position is sequentially before the first locked position in the first direction.

Abstract: A shift mechanism for a dual clutch transmission employs a rotating barrel cam having at least three tracks which are engaged by and translate at least three associated cam followers. The cam followers extend from shift fork bodies which slide on rails and include shift forks which bi-directionally translate at least three synchronizer clutches which engage at least five forward gears or speeds and reverse. A single electric motor and gear train drive the barrel cam.

Abstract: A gear shift device is used in a transmission of an engine, and includes: a shift drum that changes a speed change stage of the transmission according to a rotational position about an axis; an actuator having a driving shaft substantially orthogonal to this shift drum; a worm shaped barrel cam that is arranged parallel to the driving shaft of this actuator and that has a cam groove on an outer circumference; and a wheel gear that is coaxially fixed on the shift drum and that has a plurality of pins on an outer circumference. At least a pair of each pin of the wheel gear and the cam groove of the barrel cam is engaged with each other, and the shift drum is rotated by the actuator via the barrel cam and the wheel gear, to thereby change the speed change stage of the transmission.

Abstract: A mechanical transmission gear shifting assembly connected to a transmission with multiple gear selectors that, when moved in a back and forth motion, selects different gear ratios via a cam with a cam follower for moving gear selectors, in response to the same active cam surfaces. The assembly additionally includes a retractable stop dog, and detents for moving, stopping and holding the cam at all times, such that the cam moves in increments corresponding to sequentially increasing or decreasing selected gear states of the transmission.

Abstract: A shifting apparatus for a double clutch transmission may include a plurality of odd-numbered stage driven-shift elements, a plurality of even-numbered stage driven-shift elements, odd-numbered stage driving-shift elements that are provided to selectively move straight any one of the odd-numbered stage driven-shift elements, even-numbered stage driving-shift elements provided to selectively move straight any one of the even-numbered stage driven-shift elements, an odd-numbered stage selecting actuator that supplies the straight motion path to the odd-numbered stage driving-shift elements, an odd-numbered stage shifting actuator that supplies the rotary motion path to the odd-numbered stage driving-shift elements, an even-numbered stage selecting actuator that supplies the straight motion path to the even-numbered stage driving-shift elements, and an even-numbered stage shifting actuator that supplies the rotary motion path to the even-numbered stage driving-shift elements.

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 multistage transmission includes a swing claw member having a pin-receiving portion adapted to receive a pin member and an engaging claw portion on respective sides opposite to each other with respect to swing center, and swung by the advancement and retraction of the pin member to allow the engaging claw portion to establish engagement and release the engagement; and biasing means for biasing the swing claw member in a swing direction of bringing the engaging claw portion into engagement. The biasing means is a compression spring interposed between the inner surface of the engaging claw portion of the swing claw member and the opposing surface of the gear shaft. The multistage transmission uses multiple swing claw members of the same kind, instead of swing claw members of different kinds.

Abstract: A multistage transmission is provided that smoothly operates with a small force without the necessity of a shift clutch, that does not cause a loss of switching time during shifting, and that does not cause escape of a driving force as well as provides a small shift shock. When shift drive means executes upshift to a one-step-upper speed-change stage reduced in reduction ratio by one stage, normal rotation odd-numbered stage cam rods Cao and normal rotation even-numbered stage cam rods Cae alternately operate normal rotation odd-numbered stage engaging members Rao and the normal rotation odd-numbered stage engaging members Rae for shifting.

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 shift-drum apparatus for a gear-type transmission including a plurality of shift forks and a shift drum provided at its outer peripheral surface with a plurality of shift grooves, in which a state of the gear-type transmission is shifted between a neutral state and a plurality of transmission gear stages. The number of shift forks is the same as the number of the transmission gear stages, and each of the shift grooves includes one or more gear-shifting recesses that are depressed in an axial direction of the shift drum. The shift forks are biased in the axial direction respectively by springs toward the corresponding gear-shifting recesses. Two of the gear-shifting recesses are formed in at least one of the shift grooves, while two of the shift forks are engaged with the shift groove.

Abstract: In a transmission for a saddle type vehicle wherein a shift position sensor for detecting the angular position of a shift drum has a sensor shaft disposed coaxially with the shift drum and wherein an engaging pin disposed along a plane orthogonal to the center axis of the sensor shaft and inserted and passed through and fixed to the sensor shaft is engaged with an engagement groove provided at one axial end of the shift drum, to restrain abrasion or torsion from occurring between the engagement groove and the engaging pin even if a radial load is exerted on the shift drum at the time of a shift change and thereby to promise enhanced durability. The longitudinal direction of the engagement groove is set in a direction orthogonal to the direction in which the greatest one of radial loads on the shift drum is exerted.

Abstract: Output gears are disposed so as to be movable toward and counter to plural second input gears to which rotation of the motor is transmitted, and so as to be biased toward the plural second input gears. A cam, which has plural recesses provided at the periphery thereof, is disposed at the inside of the output gear. The cam is rotated, and a pin of the output gear enters the recess, so that the output gear is moved toward the second input gear, and the output gear is engaged with the second input gear.

Abstract: The present invention relates to a multistage automatic transmission comprising: a main body housing; an input shaft which is rotatably arranged in the main body housing and which rotates by an engine torque; a plurality of input side driving gears which have steps along the axial line of the input shaft and which are arranged into a pyramid shape to rotate together with the input shaft; a plurality of output side slave gears which have steps to correspond to the respective input side driving gears in directions opposite from one another; which engage with the respective input side driving gears, which are arranged into a pyramid shape, and the interior of which have a cam space; an output shaft arranged in the plurality of output side slave gears to receive power from the input shaft; and a shift control unit which is arranged in the cam space to selectively interconnect the output haft and the output side slave gear which receives power from any one of the plurality of input side driving gears, and to contr

Abstract: A transmission for a vehicle is disclosed. The transmission has a reverse gear locking device that includes a rotating shaft having a longitudinal axis, the rotating shaft adapted for rotational movement about its longitudinal axis, and a lock connected to the rotating shaft and positioned in alignment with a stopper extending from the shift drum of the transmission. The initial position of the lock prevents the shift drum from engaging the reverse gear. A rotational movement of the rotating shaft tilts the lock out of alignment with the stopper and allows the shift drum to engage the reverse gear.

Abstract: A gear-shifting structure is provided for a vehicle. The vehicle includes a transmission box that contains therein a gear train, a clutch, a switching fork, a gear-shifting hub, and a motor. The motor cooperates with a worm shaft to actuate the clutching operation of the clutch and to cause movement of the gear-shifting hub in order to carry out the gear shifting operation. The motor has a rotary member that drives the worm shaft on which a worm and a cam are mounted. To effect gear shifting, the motor drives the worm shaft to have the cam abut and displace the clutch and at the same time, the worm drives the gear-shifting hub to thus realize the operation of gear shifting.

Abstract: Multiple gear changes can easily be achieved by means of a straightforward and simple mechanical method, power transmission efficiency and the gear-changing sensation can be improved as compared with the prior at, and, in addition, fuel consumption can actually be reduced even as power performance is increased.

Abstract: A differential gear assembly is disclosed. The differential gear assembly includes a first sun gear and a second sun gear coaxially aligned with each other; a first set of planetary gears in mating engagement with the first sun gear; and a second set of planetary gears in mating engagement with the second sun gear. The first and second sets of planetary gears are in mating engagement with each other. The differential gear assembly also includes a first set of friction members, each of which faces a respective one of axial ends of the first set of planetary gears; and a second set of friction members, each of which faces a respective one of axial ends of the second set of planetary gears. The differential gear assembly further includes a first body connecting at least a plurality of said first set of friction members together, and a second body connecting at least a plurality of said first set of friction members together.

Abstract: A power transmitting apparatus can be configured to switch between 2-wheel drive mode and 4-wheel drive mode and to lock and unlock a differential device. The power transmitting apparatus can comprise an input shaft connected to a driving power source i.e.

Abstract: An outer circumference of a shift drum of a vehicle transmission is provided with at least one particular lead groove among multiple lead grooves which continuously extends beyond one circle of the shift drum. Two ends of the particular lead groove are arranged so as to be out of alignment with each other in the axial direction of the shift drum. A common shift position adapted to establish gear trains with two shift stages different from each other is set at one position corresponding to the two ends of the particular lead groove along the circumferential direction of the shift drum. The resulting configuration prevents an increase in the diameter of a shift drum and eliminates the significant change of the shape of a lead groove, even as the number of shift positions set on the shift drum is increased.

Abstract: A twin clutch type speed-change apparatus for detecting the engagement state of a dog clutch by use of the rotational speed difference between an inner main shaft and an outer main shaft and of a signal outputted from a gear position sensor. A rotational speed difference between an inner main shaft and an outer main shaft is detected by use of inner and outer rotational speed sensors. When the engagement of the dog clutch is to be released, it is judged to complete the release if the signal outputted from the gear position sensor indicates a speed step number after shifting and the rotational speed difference is zero. It is judged as a dog-tip caught state if the signal outputted from the gear position sensor indicates a speed step number before or after shifting and the rotational speed difference is a transmission gear ratio difference.

Abstract: A multi-gear-speed transmission includes cam rods in sliding contact with an inner peripheral surface of an inner cavity of a gear shaft; pin members inserted in pin holes bored in the gear shaft in the radial directions and which are advanced or retreated by alternatedly making contact with the sliding contact surfaces of the cam rods and cam grooves. Swing claw members are rotatably supported on pivot pins provided in the gear shaft and which are advanced or retracted by the pin members to be engaged with or disengaged from gears (n). The swing claw members and the pivot pins are embedded in recessed parts formed in the outer periphery of the gear shaft, annular bearing collar members externally fitted over the gear shaft are arranged to press the pivot pins from the outer side, and the gears (n) are rotatably borne on the bearing collar members.

Abstract: A four-wheel-drive-vehicle driving force distribution apparatus has an auxiliary transmission mechanism for switching motive power transmitted to an input shaft at least between two levels, a high speed and a low speed, and transmitting the motive power to a main output shaft; a friction clutch for selectively transmitting the motive power of the main output shaft to an auxiliary output shaft; a ball cam mechanism for changing the pressing force of the friction clutch in a non-step manner; and a shift mechanism for shifting the auxiliary transmission mechanism. A clutch control mechanism is provided between a drive member fixed to an output shaft of a motor and a pinion gear and changes the clutch pressing force caused by the ball cam mechanism corresponding to clockwise rotation of the drive member performed by a motor starting from a control starting point.

Abstract: A bicycle clutch comprises a transmission shaft, at least two gears, at least two slide blocks, at least two clutch blocks, at least two guiding blocks, a switch shaft and a stationary shaft. The gears and the slide blocks are coaxially disposed on the transmission shaft. The sliding blocks, switch shaft and stationary shaft are coaxially assembled. The clutch blocks are disposed on the transmission shaft, the gears and the slide blocks. The guiding blocks are disposed on the switch shaft and the slide blocks. Through angle deflection, the clutch can selectively make one of the gears engage with the driven assembly to change the rotation speed.

Abstract: A method of forming a gearbox includes the use of hollow structural steel.

Abstract: A reverse drive assembly for a motorcycle that includes a transmission assembly having a main shaft and a counter shaft. The reverse drive assembly includes a first drive member configured to be coupled to an opposite end of the main shaft, a second drive member configured to be coupled to a second end of the counter shaft, and an engagement member operatively positioned between the second drive member and the counter shaft. The engagement member is movable between a first position out of engagement with the second drive member and the counter shaft, and a second position in engagement between the second drive member and the counter shaft to drive the counter shaft in a reverse direction. In some constructions, the engagement member is operatively positioned between the first drive member and the main shaft.

Abstract: The present invention broadly comprises a gear selector assembly including a tube with at least one engagement feature, arranged to be disposed within a drive shaft for a transmission, the transmission including at least one gear and the drive shaft including at least one gear actuation assembly; and a differential rotation element coupled with the tube and arranged to be coupled with the drive shaft so that the tube is differentially rotatable with respect to the drive shaft. The tube is arranged to differentially rotate such that the engagement feature engages the actuation assembly and the transmission engages a respective gear from the at least one gear. The assembly includes a means for displacing a portion of the differential rotation element such that the tube axially and rotationally displaces with respect to the drive shaft. The portion axially and rotationally engages with an interface element to controllably position the tube.

Abstract: The present invention provides a shift-drum apparatus for a gear-type transmission including a plurality of shift forks and a shift drum provided at its outer peripheral surface with a plurality of shift grooves, in which a state of the gear-type transmission is shifted between a neutral state and a plurality of transmission gear stages. The number of the shift forks is the same as the number of the transmission gear stages, and each of the shift grooves includes one or more gear-shifting recesses that are depressed in an axial direction of the shift drum. The shift forks are biased in the axial direction respectively by springs toward the corresponding gear-shifting recesses. Two of the gear shifting recesses are formed in at least one of the shift grooves, while two of the shift forks are engaged with the shift groove.

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: To reduce the engaging sound to a low level, generated at the time of changing over the change gear stage by sliding a shifter, an intermittent feed mechanism includes a drum shifter, a pair of pawls symmetrically mounted to the drum shifter and energized in tilting-up directions, engaging recesses provided at regular intervals along the circumferential direction at the inner periphery of a shift drum center so as to be capable of engagement with both the pawls, and a fixed guide plate for guiding the tilted conditions of both the pawls. The guide plate is provided with a large-diameter arcuate part, a small-diameter arcuate part, and connecting parts. The pawls are engaged with the engaging recesses by the connecting parts, in the course of turning of the drum shifter by a turning amount necessary for changing over the establishment conditions of a plurality of change gear stages of gear trains.

Abstract: A stepper motor driven actuator that eliminates the need for a position sensor is provided. The stepper motor rotates a cam in a control piston valve. In a single nozzle embodiment, pressure balance is maintained by a spring preload on one end of the piston in one embodiment, and by hydraulic pressure acting on a double diameter end portion of the piston in another embodiment. As the cam is rotated, the change in the gap between the nozzle and the cam changes the pressures on the control piston ends, which forces the piston in the direction that will re-equalize the pressure based on the cam-nozzle gap. As a result, the head or rod of the actuator piston receives high pressure flow, thereby moving the actuator. Movement of the actuator rod provides mechanical feedback to the cam, causing the cam to move back to its mechanical null position.

Abstract: A vehicular transmission for an internal combustion engine includes lead grooves disposed on an outer periphery of a shift drum having 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 power transmission device for a motor vehicle includes a clutch for transferring torque between first and second shafts. A clutch actuation system includes a drive member and a cam member in cooperation with one another. The drive member is driven by an electric motor and includes first and second rollers rotatably mounted thereon. The cam member includes first and second circumferentially extending channels, each having a continually reducing radius. The first and second channels are separate from and overlap one another. The first roller is positioned within the first channel to engage the drive member and the cam member. The second roller is positioned within the second channel to engage the drive member and the cam member such that relative rotation between the drive member and the cam member translates the cam member along an axis of relative rotation to vary the force applied to the clutch.

Abstract: A shift control device in which a number of times that an angle change amount per a defined time period is successively equal to or less than a determined value is calculated, when a rotation angle of a shift shaft is equal to or more than a threshold value. In addition, an abutting state determination is performed that determines whether the number of times is equal to or above a threshold value, and if it is determined that there is an abutting state (namely, the shift shaft has reached an actual mechanical maximum rotation angle), processing shifts to an engagement process of a shift clutch.

Abstract: A multi-stage transmission has driving gears m and driven gears n supported on a hollow driven gear shaft 12. The driven gears n are individually engageable with and disengageable from the hollow driven gear shaft 12. The driving and driven gears m, n mesh constantly. The transmission is intended to realize a smooth speed change by providing cam rods 21,22 within the driven gear shaft 12 for engagement and disengagement between the driven gears n and the driven gear shaft 12 and by providing compact lost motion mechanisms 52, 53 for the cam rods, respectively. There are provided swing pawl members 24, 25 each of which disengageably engages projections 30 formed at circumferentially spaced positions on the inner peripheral surface of each driven gear n to control engagement and disengagement between each driven gear n and the driven gear shaft 12. The cam rods 21, 22 are moved in the driven gear shaft 12 to operate the swing pawl members 24, 25.

Abstract: A shift position changing drive member for a transmission includes an arm member capable of turning around the axis of a shift spindle for drivingly turning a shift drum in response to the turning of the shift spindle wherein the shift drum is prevented from coming into a neutral position even if the shifting speed is stopped in midstream. A lost motion spring includes gripping portions gripping a pressing portion from both sides of a coil portion surrounding the shift spindle. An arm member of shift position changing drive member is provided with a pressure-receiving member which is gripped by both gripping portions in such a manner that when the turning member is turned, if, in response to the turning direction, the pressing portion abuts against one of the gripping portions for turning, the other of the gripping portions abuts against the pressure-receiving member.

Abstract: The driving force can be transmitted at the time of both acceleration and deceleration in an engaged state where a first engagement face of a strut is forced to protrude inside a cutaway of a gear. The driving force is transmitted at the time of acceleration and the transmission of the driving force can be cut off at the time of deceleration in a one-way state where the first engagement face of the strut and the cutaway of the gear are made either to engage with or to disengage from each other in accordance with the rotational direction of the gear relative to the rotational shaft. The transmission of the driving force can be cut off at the time of both acceleration and deceleration in a disengaged state where the first engagement face of the strut is forced to withdraw from the cutaway of the gear. In addition, the decreasing of the transmission efficiency caused by friction between the strut and the gear can be prevented.

Abstract: The invention relates to a gear actuator for a motor vehicle transmission design, that has several ratio steps for forming gears, whereby the gear actuator has a gear-shift shaft that is mounted so that it can rotate for the shifting of gears and that is mounted so that it can slide axially for the selection of gears and whereby the gear actuator also has a shift gate, whereby the shift gate also has a fixed mounted first shift gate part that is especially a shaft or an axle, as well as a second shift gate part that is mounted so that it can move axially and move in rotation or swivel, which is especially a disk or plate and is coupled with the gear-shift shaft and whereby the first shift gate part has several axially spaced recesses, into which the second shift gate part can be swiveled depending on its axial position.

Abstract: A shift actuator disposed outside a power unit that is easily positioned in the neutral position during mounting. A motorcycle equipped with a shift actuator includes a transmission; a shift shaft for changing the gears of the transmission; and a crankcase that covers the shift shaft and the transmission. The shift actuator includes a motor; an output shaft connected to the shift shaft with a connecting device therebetween; a worm gear interposed between the motor and the output shaft; a case supporting the motor, the output shaft, and the worm gear; and a potentiometer supported by the case and sensing the position of the output shaft. The worm gear transfers a driving force from the motor to the output shaft but transfers no driving force from the output shaft to the motor.

Abstract: A multistage transmission includes a lost motion mechanism for regulating the operation for a downward shift in acceleration and for an upward shift in deceleration. Regulating rods are integrally moved with a control rod. A cutout into which a pin can be fitted together with a cam groove of the slidingly touched cam rod is formed corresponding to each cam groove in the regulating rods. The cutout of the regulating rods corresponding to the cam groove of the cam rod for normal rotation is formed longer than the corresponding cam groove on the reverse side to a moving direction of the control rod in an upward shift in a state in which shifted speed is established. The cutout of the regulating rods corresponding to the cam groove of the cam rod for reverse rotation is formed longer than the corresponding cam groove on the reverse side to a moving direction.

Abstract: A power unit includes a shaft member rotatably supported by the crankcase and a torsional coil spring, disposed at one end of the shaft member, biasing a swing arm in one rotational direction. An oil strainer is fixed to the crankcase through a strainer support bracket extending vertically relative to a strainer element. The torsional coil spring includes a coil portion wound around the shaft member, one end portion retained on the side of the shaft member, and the other end portion retained by a retaining portion formed integrally with the strainer support bracket.

Abstract: An automatic transmission has a park system with a shaft and a parking pawl. The shaft rotates in response to a gear shift lever, and a detent lever positions the parking pawl in response to rotation of the shaft. A detent spring assembly biases the detent lever and has a detent spring, cage, and roller assembly. The cage aligns the roller assembly, while the detent spring is connected to the cage at one end and has a flat reaction surface formed at a second end. A cage notch portion aligns the cage with the detent lever, and the roller assembly into a perpendicular orientation with detent lever teeth. The notch portion engages either a detent tooth or a stationary portion of an internal mode switch (IMS). A shaft inserts into a roller through a side hole in the cage to retain the roller assembly therewithin.

Abstract: Disclosed is a constantly-meshing-type multi-stage transmission which can be operated with small forces, does not need a clutch for gear shift, has no loss of changeover time at the time of gear shift, and in which a loss of the driving force is prevented. Driven gears n1, n2, . . . n5 are supported on a hollow driven gear shaft 12 in a manner engageable with and disengageable from a hollow driven gear shaft 12 via swing pawl members 24, 25. The transmission has first engaging means 25 for engaging the gear shaft 12 with a first driven gear n1, so as to effect synchronous rotation thereof; and second engaging means 25 for engaging the gear shaft 12 with a second gear n2, one step lower in reduction gear ratio than the first gear n1, so as to effect synchronous rotation thereof.

Abstract: A straddle-type four wheeled vehicle according to the present invention includes: a gear-type transmission capable of switching forward/backward traveling gears; a change drum, which is disposed substantially in parallel to a crankshaft of an engine and is turned at every predetermined angle to thus change the gear of the gear-type transmission; and a reverse lock device. The reverse lock device has: a stopper rotated integrally with the change drum; a reverse lock pin disposed substantially perpendicularly to an axial direction of the change drum and capable of moving in a direction of a pin length between a lock position, at which the reverse lock pin is locked to the stopper so as to prevent the change drum from being rotated to a backward traveling position, and an unlock position, at which the reverse lock pin is unlocked from the stopper; and an unlocking transmission mechanism for moving the reverse lock pin to the unlock position.

Abstract: A gear-shifting safety device is provided for an all-terrain vehicle (ATV), including a gear lever, a gear-shifting hub shaft, a gear-shifting gear set, and a reversing bar. An end of the gear-shifting hub forms a step on which a block is provided. The block and the step form a stop face therebetween. The reversing bar has an end forming a stop section that is positionable on the step and is selectively in abutting engagement with the stop face so that to change to the reversing position, the reversing bar must be first actuated to disengage the stop section thereof from the stop face, allowing the switching fork to move to the reversing position on a position chute of the gear-shifting hub, thereby eliminating the damage of accidentally switching to reversing during the forward movement of the vehicle.

Abstract: A transmission mechanism is provide that can be interposed between a shift actuator and a shift shaft. The mechanism can include first and second coupling parts that can be coupled for movement relative to each other; a biasing mechanism that can be configured for urging the first and second coupling parts toward a neutral position; and a stopper mechanism that can be configured for stopping the relative movement of one of the first and second coupling parts when moved relatively from the neutral position against urging force of the biasing mechanism. When the shift actuator is stroked by a predetermined amount, a dog can be compulsorily disengaged as the first and second coupling parts are moved together by the stopper mechanism, and engaged as one of the first and second coupling parts moves relatively against the urging force, for allowing smooth shift change.

Abstract: A vehicle shifting mechanism configured for actuation of a clutch and gear-shifting of a shift drum in a transmission is disclosed, which includes a camshaft linked to the shift drum; an actuating motor for driving the camshaft to allow the camshaft to make one revolution to shift the shift drum with one gear; and a cam connected to the camshaft to coaxially rotate with the camshaft and abutting against a release bearing actuating element to actuate engagement and disengagement of the clutch. The cam has a symmetrical contour such that the camshaft driven by the actuating motor is capable of making one unidirectional revolution to enable actuation of the clutch and the gear-shifting of the shift drum to occur concurrently.

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: A method for controlling a gear-shifting process from an initial gear to a target gear in a manual transmission with active interlock. According to the method, the active interlock gear-shifting mechanism includes at least one shifting finger which co-operates with a selector fork, and has a layout geometry including a finger and a cam. The method contains the following steps: the selector fork of the initial gear is brought into a reliable shifting position by a method for compensating errors on the gear shifting mechanism, and/or the selector fork of the target gear is brought into a reliable shifting position a method for compensating errors on the gear shifting mechanism, before the target gear is engaged, when ever a temporarily non-critical gear-shift is to be carried out.