Abstract: A switching device of a driving power transmission system equipped in an off-road vehicle, including a switching lever configured to switch driving power transmission of the driving power transmission system, and a negative-pressure actuator module that is coupled to the switching lever and is configured to operate the switching lever.

Abstract: A wet brake system for a vehicle including a case; an internal operation lever disposed inside the case; a hydraulic cylinder which is integrally mounted to the case and is configured to actuate the internal operation lever; and a brake mechanism configured to be operated by the actuation of the internal operation lever by the hydraulic cylinder to apply a braking force to an axle of the vehicle.

Abstract: A four-wheeled utility vehicle including an engine unit mounted in the utility vehicle; and a vehicle body frame including a frame member that is disposed in the vicinity of the engine unit and is partially movable relative to the engine unit.

Abstract: To provide a drive transmission changer for a dog clutch of a vehicle, which is effective to achieve change of the drive transmission assuredly without requiring any complicated control and which can be assembled compact in size. The drive transmission changer includes a drive motor 1, an output shaft 2 including a shaft body 2a and an eccentric stud 2b, a gear 3 mounted on the shaft body 2a for rotation relative thereto and drivingly coupled with the drive motor 1, a first transmission member 4 rotatable together with the gear 3, a second transmission member 5 mounted on the shaft body 2a for rotation together therewith, and a torsion coil spring 6 operatively coupled between the first and second transmission members 4 and 5 and arranged coaxially with the shaft body 2a for accumulating a drive force as the first transmission member 4 rotates.

Abstract: A switching device of a driving power transmission system equipped in an off-road vehicle, including a switching lever configured to switch driving power transmission of the driving power transmission system, and a negative-pressure actuator module that is coupled to the switching lever and is configured to operate the switching lever.

Abstract: A wet brake system for a vehicle including a case; an internal operation lever disposed inside the case; a hydraulic cylinder which is integrally mounted to the case and is configured to actuate the internal operation lever; and a brake mechanism configured to be operated by the actuation of the internal operation lever by the hydraulic cylinder to apply a braking force to an axle of the vehicle.

Abstract: To provide a drive transmission changer for a dog clutch of a vehicle, which is effective to achieve change of the drive transmission assuredly without requiring any complicated control and which can be assembled compact in size. The drive transmission changer includes a drive motor 1, an output shaft 2 including a shaft body 2a and an eccentric stud 2b, a gear 3 mounted on the shaft body 2a for rotation relative thereto and drivingly coupled with the drive motor 1, a first transmission member 4 rotatable together with the gear 3, a second transmission member 5 mounted on the shaft body 2a for rotation together therewith, and a torsion coil spring 6 operatively coupled between the first and second transmission members 4 and 5 and arranged coaxially with the shaft body 2a for accumulating a drive force as the first transmission member 4 rotates.

Abstract: A four-wheeled utility vehicle including an engine unit mounted in the utility vehicle; and a vehicle body frame including a frame member that is disposed in the vicinity of the engine unit and is partially movable relative to the engine unit.

Abstract: A geared motor comprising an electric motor, a reduction gear having an input connected to a rotational shaft of the electric motor, an output shaft connected to an output stage gear of the reduction gear, which has a coupling member of resilient material attached thereto and a position sensor for detecting a rotational angle position of the output shaft, which has an input shaft connected to the output stage gear through the coupling member wherein the output stage gear has a protrusion imbedded in the coupling member so as to reinforce the coupling member and prevent it from being twisted whereby there occurs no difference between a rotational angle of the output shaft and that of the input shaft of the position sensor.

Abstract: A geared motor comprising an electric motor, a reduction gear having an input connected to a rotational shaft of the electric motor, an output shaft connected to an output stage gear of the reduction gear, which has a coupling member of resilient material attached thereto and a position sensor for detecting a rotational angle position of the output shaft, which has an input shaft connected to the output stage gear through the coupling member wherein the output stage gear has a protrusion imbedded in the coupling member so as to reinforce the coupling member and prevent it from being twisted whereby there occurs no difference between a rotational angle of the output shaft and that of the input shaft of the position sensor.

Abstract: A variable-speed V-belt drive includes: a drive pulley; a driven pulley including a fixed sheave with a cylindrical shaft and a movable sheave mounted on the cylindrical shaft so that the movable sheave can rotate and axially move; a V belt extended between the drive and driven pulleys; and a pressure mechanism of applying pressure to the movable sheave of the driven pulley. The pressure mechanism includes a helical cam groove formed in one of the cylindrical shaft and the movable sheave of the driven pulley, and a roller mounted on other of the cylindrical shaft and the movable sheave of the driven pulley so that the roller engages with the cam groove. The cam groove has opposite first and second working surfaces. The second working surface has a retaining surface of retaining the roller thereon when the vehicle travels in the engine-braking mode. The variable-speed V-belt drive can maintain the effect of engine brake at a high level even when traveling down a steep hill.

Abstract: A straddle type four-wheeled all-terrain vehicle includes: an engine mounted on a body frame and disposed between front wheels and rear wheels, having a crankcase; a variable-speed V-belt drive disposed on a side of the crankcase and covered with a V-belt drive cover, the V-belt drive cover having an upper wall provided with a cooling air discharge port opening upward; and a cooling air exhaust duct disposed within a right-and-left width of the body frame. The cooling air exhaust duct communicates with the cooling air discharge port and has an air outlet located in front of a seat so that a cooling air is discharged through the air outlet into a space under the seat. Cooling air is discharged through the air outlet of the cooling air exhaust duct into a space under the seat.

Abstract: A wheel driving system is capable of varying differential limiting torque applied to a differential included in an all-terrain vehicle according to the difference between loads respectively applied to the right and the left wheel of the vehicle, which varies depending on the traveling condition or turning condition of the vehicle. Right and left wheels are connected through a differential gear mechanism (30) having a differential case (46) and held in a reduction gear case (13), an input pinion (22) and a drive shaft to an engine. The differential case (46) and a differential gear shaft (36) connected to the wheel are interlocked by a wet multiple-disk differential limiting mechanism (31) having a friction clutch mechanism immersed in oil. The multiple-disk differential limiting mechanism (31) is operated by a multiple-disk differential limiting mechanism operating mechanism to vary differential limiting torque.

Abstract: A selective four-wheel drive transmission system includes a dog clutch (48) to be engaged and to be disengaged to set the selective four-wheel drive transmission system for a four-wheel drive mode and a two-wheel drive mode, respectively. The dog clutch (48) has a moving sleeve (52) provided with projections (51), and a coupling member (50) provided with recesses (57). An electric motor (53) internally provided with a potentiometer (54) shifts the moving sleeve (52) between a disengaging position (A0) and an engaging position (A2) to engage and disengage the dog clutch (48). A controller controls the electric motor (53) on the basis of a signal provided by the potentiometer (54) and indicating the position of the moving sleeve (52) to move the moving sleeve (52).

Abstract: In an engine brake control method for a vehicle provided with a variable-speed V-belt drive including a drive pulley having a movable sheave, a driven pulley, and a V belt extended between the drive pulley and the driven pulley, a position of an engine brake regulating member is detected by a detector. The engine brake regulating member limits an extent of an outward axial movement of the movable sheave of the drive pulley so as to regulate a maximum V-groove width of the drive pulley. A position of the engine brake regulating member is controlled by a controller based on a position signal sent from the detector to the controller. The controller operates an actuator to move the engine brake regulating member so that the engine brake regulating member is located at a desired position relative to the movable sheave of the drive pulley.

Abstract: In an engine brake control method for a vehicle provided with a variable-speed V-belt drive including a drive pulley having a movable sheave, a driven pulley, and a V belt extended between the drive pulley and the driven pulley, a position of an engine brake regulating member is detected by a detector. The engine brake regulating member limits an extent of an outward axial movement of the movable sheave of the drive pulley so as to regulate a maximum V-groove width of the drive pulley. A position of the engine brake regulating member is controlled by a controller based on a position signal sent from the detector to the controller. The controller operates an actuator to move the engine brake regulating member so that the engine brake regulating member is located at a desired position relative to the movable sheave of the drive pulley.

Abstract: A selective four-wheel drive transmission system includes a dog clutch (48) to be engaged and to be disengaged to set the selective four-wheel drive transmission system for a four-wheel drive mode and a two-wheel drive mode, respectively. The dog clutch (48) has a moving sleeve (52) provided with projections (51), and a coupling member (50) provided with recesses (57). An electric motor (53) internally provided with a potentiometer (54) shifts the moving sleeve (52) between a disengaging position (A1) and an engaging position (A2) to engage and disengage the dog clutch (48). A controller controls the electric motor (53) on the basis of a signal provided by the potentiometer (54) and indicating the position of the moving sleeve (52) to move the moving sleeve (52).

Abstract: A variable-speed V-belt drive includes: a drive pulley; a driven pulley including a fixed sheave with a cylindrical shaft and a movable sheave mounted on the cylindrical shaft so that the movable sheave can rotate and axially move; a V belt extended between the drive and driven pulleys; and a pressure mechanism of applying pressure to the movable sheave of the driven pulley. The pressure mechanism includes a helical cam groove formed in one of the cylindrical shaft and the movable sheave of the driven pulley, and a roller mounted on other of the cylindrical shaft and the movable sheave of the driven pulley so that the roller engages with the cam groove. The cam groove has opposite first and second working surfaces. The second working surface has a retaining surface of retaining the roller thereon when the vehicle travels in the engine-braking mode. The variable-speed V-belt drive can maintain the effect of engine brake at a high level even when traveling down a steep hill.

Abstract: A straddle type four-wheeled all-terrain vehicle includes: an engine mounted on a body frame and disposed between front wheels and rear wheels, having a crankcase; a variable-speed V-belt drive disposed on a side of the crankcase and covered with a V-belt drive cover, the V-belt drive cover having an upper wall provided with a cooling air discharge port opening upward; and a cooling air exhaust duct disposed within a right-and-left width of the body frame. The cooling air exhaust duct communicates with the cooling air discharge port and has an air outlet located in front of a seat So that a cooling air is discharged through the air outlet into a space under the seat. Cooling air is discharged through the air outlet of the cooling air exhaust duct into a space under the seat.

Abstract: A wheel driving system is capable of varying differential limiting torque applied to a differential included in an all-terrain vehicle according to the difference between loads respectively applied to the right and the left wheel of the vehicle, which varies depending on the traveling condition or turning condition of the vehicle. Right and left wheels are connected through a differential gear mechanism (30) having a differential case (46) and held in a reduction gear case (13), an input pinion (22) and a drive shaft to an engine. The differential case (46) and a differential gear shaft (36) connected to the wheel are interlocked by a wet multiple-disk differential limiting mechanism (31) having a friction clutch mechanism immersed in oil. The multiple-disk differential limiting mechanism (31) is operated by a multiple-disk differential limiting mechanism operating mechanism to vary differential limiting torque.