Abstract: Pressure-side cam portions of a pressure plate each include a pressure-side assist cam portion including a pressure-side assist cam surface, a pressure-side body located between the pressure-side assist cam portion and a pressure-side slipper cam portion, and a first stepped portion between a main outer circumferential surface of the pressure-side body and a sub outer circumferential surface of the pressure-side assist cam portion. The sub outer circumferential surface is located radially inward of the main outer circumferential surface. The sub outer circumferential surface is inclined radially inward in a second direction. Among portions of the main outer circumferential surface, at least a stepped portion-side outer circumferential surface adjacent to the first stepped portion is inclined radially outward in the second direction.

Abstract: Pressure-side cam portions of a pressure plate each include a pressure-side assist cam portion including a pressure-side assist cam surface, a pressure-side body located between the pressure-side assist cam portion and a pressure-side slipper cam portion, and a first stepped portion between a main outer circumferential surface of the pressure-side body and a sub outer circumferential surface of the pressure-side assist cam portion. The sub outer circumferential surface is located radially inward of the main outer circumferential surface. The sub outer circumferential surface is inclined radially inward in a second direction. Among portions of the main outer circumferential surface, at least a stepped portion-side outer circumferential surface adjacent to the first stepped portion is inclined radially outward in the second direction.

Abstract: In a power transmission apparatus, an auxiliary clutch plate different in diameter from driving and driven clutch plates located in a clutch housing. When the driving and driven clutch plates are pressed against each other, the auxiliary clutch plate is pressed to enable transmission of a driving force of an engine to a driving wheel. When a pressing force exerted on the driving and driven clutch plates is released, a pressing force exerted on the auxiliary clutch plate is released to cut off transmission of the driving force of the engine to the driving wheel.

Abstract: A clutch device includes a clutch center holding output-side rotating plates alternately arranged with input-side rotating plates, and a pressure plate movable toward or away from the clutch center. The pressure plate includes pressure-side fitting teeth holding the output-side rotating plates. The clutch center includes center-side fitting teeth holding the output-side rotating plates. In a half-clutch state, a portion of one of the center-side fitting teeth overlap with a portion of one of the pressure-side fitting teeth when seen in the radial directions of an output shaft.

Abstract: In a power transmission apparatus, a second clutch includes a divider dividing driving clutch plates and driven clutch plates in an axial direction such that a first region adjacent to a clutch pressure plate and a second region adjacent to a centrifugal clutch are defined. The second clutch presses the driving clutch plates and the driven clutch plates in the first region and the second region against each other during operation of the centrifugal clutch, and presses the driving clutch plates and the driven clutch plates in the first region against each other during operation of a back torque transmission cam.

Abstract: In a power transmission apparatus, a centrifugal clutch includes a holder, a press, and springs to urge masses from a radially outer position to a radially inner position. The masses are each housed in an associated one of housing portions arranged in a circumferential direction of the holder such that the masses are radially movable. More than one spring is provided in the circumferential direction between an inner peripheral wall surface of each of the housing portions and an associated one of the masses to urge the associated mass from the radially outer position to the radially inner position.

Abstract: Provided are a joint component formed with fine recessed portions, a multiplate clutch device including the joint component, and a joint component manufacturing method. At the joint component, many fine recessed portions are formed at a joint surface joined to a joint object. The joint surface is formed in a circular ring shape along a peripheral direction of the base body, and is formed with a flatness of equal to or less than 0.15 mm. The fine recessed portions are formed at the joint surface such that adjacent ones of the fine recessed portions do not overlap with each other and a formation density per unit area at the joint surface is uniform. The fine recessed portions are formed as laser processing marks formed at the base body by irradiation with laser light.

Abstract: A power transmission apparatus a centrifugal clutch including a holder and a press. The holder and the press are each circumferentially provided with protrusions fitted and attached to cut-outs of a clutch housing. The holder is an integrated assembly into which a mass that is being held is integrated. The integrated assembly and the press are non-connected separate components and are independently movable toward or away from each other.

Abstract: A power transmission device has an interlocking member 9 moving a pressure member 5 from an inactive position to an active position. A release spring (m) applies an urging force, while allowing movements of the interlocking member 9 and the pressure member 5, until drive-side clutch plates 6 and driven-side clutch plates 7 reach an engaged state before the drive-side clutch plates 6 and the driven-side clutch plates 7 are pressed against each other. A clutch spring 11 is compressed in a process where the interlocking member 9 moves after the drive-side clutch plates 6 and the driven-side clutch plates 7 have reached the engaged state. The clutch spring applying a press-contact force between the drive-side clutch plates 6 and the driven-side clutch plates 7 while allowing movements of the interlocking member 9 and the pressure member 5. The set load of the clutch spring 11 is set to be smaller than the maximum load of the release spring (m).

Abstract: A power transmission device has an interlocking member 9 moving a pressure member 5 from an inactive position to an active position. A release spring (m) applies an urging force, while allowing movements of the interlocking member 9 and the pressure member 5, until drive-side clutch plates 6 and driven-side clutch plates 7 reach an engaged state before the drive-side clutch plates 6 and the driven-side clutch plates 7 are pressed against each other. A clutch spring 11 is compressed in a process where the interlocking member 9 moves after the drive-side clutch plates 6 and the driven-side clutch plates 7 have reached the engaged state. The clutch spring applying a press-contact force between the drive-side clutch plates 6 and the driven-side clutch plates 7 while allowing movements of the interlocking member 9 and the pressure member 5. The set load of the clutch spring 11 is set to be smaller than the maximum load of the release spring (m).

Abstract: A motor vehicle has a motor performing power driving and regeneration. The motor includes an inverter, a first power storage device suppling energy to the motor, a power converter and a circuit. The converter has a voltage step down function during the power driving and a voltage step up function during the regeneration. The power converter, with the voltage step down function during the power driving, is connected in the circuit to the first power storage device. During the power driving of the motor, the power converter steps down an output voltage of the first power storage device to supply the energy from the first power storage device to the inverter. During the regeneration in the motor, the power converter steps up a DC voltage of the inverter to recover regenerated energy into the first power storage device.

Abstract: A power transmission device has an interlocking member 9 moving a pressure member 5 from an inactive position to an active position. A release spring (m) applies an urging force, while allowing movements of the interlocking member 9 and the pressure member 5, until drive-side clutch plates 6 and driven-side clutch plates 7 reach an engaged state before the drive-side clutch plates 6 and the driven-side clutch plates 7 are pressed against each other. A clutch spring 11 is compressed in a process where the interlocking member 9 moves after the drive-side clutch plates 6 and the driven-side clutch plates 7 have reached the engaged state. The clutch spring applying a press-contact force between the drive-side clutch plates 6 and the driven-side clutch plates 7 while allowing movements of the interlocking member 9 and the pressure member 5. The set load of the clutch spring 11 is set to be smaller than the maximum load of the release spring (m).

Abstract: During movement of a mass of a centrifugal clutch a radially inner position to a radially outer position and a resulting increase in torque transmitted from an input gear to an output shaft, a power transmission apparatus includes a first torque region where the apparatus restricts operation of a pressing assist cam and a second torque region where the apparatus allows operation of the pressing assist cam.

Abstract: Provided are a wet friction plate and a wet multiplate clutch device including the wet friction plates capable of improving the performance for discharging lubricant oil adhering to surfaces of friction members. A wet friction plate includes oil grooves and friction members on a flat plate annular core metal. At a surface of a porous layer of the friction member, a friction slide surface and lubricant oil recessed portions are formed. The lubricant oil recessed portion has no sharp portion in a pointed shape, such as a corner portion, and is formed with a smooth continuous surface. The multiple lubricant oil recessed portions depressed in a recessed shape with respect to the friction slide surface are formed. In the porous layer, hollow portions are formed to have the same formation rate between a portion forming the friction slide surface and a portion forming the lubricant oil recessed portion.

Abstract: Provided are a method for manufacturing a wet friction plate, whereby efficiency of the work of forming a fine groove on a friction material can be improved, the wet friction plate, and a wet multiple-plate clutch device having the wet friction plate. In the method for manufacturing a wet friction plate 200, a core metal 201 and a friction material 210 are prepared, a resin layer 203 is formed on the core metal, the friction material is attached onto the resin layer, and a fine groove 211 is formed in the friction material. Specifically, irradiation of a laser beam L is started on an exposed portion 205 of the core metal. A laser head 301 is displaced in an annular shape while continuously emitting the laser beam. Thus, annular fine grooves 204 and 211 are formed in the exposed portion of the core metal and the friction material.

Abstract: A power transmission device has a first pressure member (5a), a second pressure member (5b) and a back-torque transmitting cam. The first pressure member (5a) presses the drive-side clutch plates (6) and the driven-side clutch plates (7) against each other. The second pressure member (5b) releases a press-contact force between the drive-side clutch plates (6) and the driven-side clutch plates (7). The back-torque transmitting cam moves the second pressure member (5b) relative to the first pressure member (5a) to keep pressing the drive-side clutch plates (6) and the driven-side clutch plates (7) against each other when a rotational force is input to the clutch member (4), via the output shaft (3), in a process where the weight member (8) moves from the radially-outer position to the radially-inner position and the first pressure member (5a) moves to follow the interlocking member (9).

Abstract: A motor vehicle has a motor performing power driving and regeneration. The motor has an inverter, a first power storage device with a large-capacity characteristic, a second power storage device with a high-power characteristic, a power converter and a circuit. The power converter has a voltage step down function during the power driving and a voltage step up function during the regeneration. In the circuit, the power converter, with the voltage step down function during the power driving, is connected to the first power storage device and the second power storage device is connected in series between a reactor of the power converter and the inverter. During the power driving of the motor, an output voltage of the first power storage device is stepped down to supply energy from the first power storage device and the second power storage device to the inverter.

Abstract: Provided are a wet friction plate and a wet multiplate clutch device capable of reduction drag torque while suppressing a decrease in the area of a friction member. The wet friction plate includes multiple friction members through oil grooves on a flat plate annular core metal. The friction member has first fine grooves opening at an inner peripheral edge of the friction member and extending to an outer peripheral edge side and second fine grooves opening at an outer peripheral edge of the friction member and extending to an inner peripheral edge side. The first fine groove and the second fine groove are formed to have a groove width of equal to or greater than 0.1 mm and equal to or less than 0.8 mm, and overlap portions overlapping with each other in a circumferential direction at the same position in a radial direction of the core metal.

Abstract: A power transmission device has a first clutch member 4a coupled to an output member 3. A second clutch member 4b has a plurality of driven-side clutch plates 7. A back-torque transmitting cam presses the drive-side clutch plates 6 and the driven-side clutch plates 7 against each other by moving the second clutch member 4b when a rotational force is input to the first clutch member 4a. A cushioning member 12 is interposed between the first clutch member 4a and the second clutch member 4b. The cushioning member 12, by being compressed, applies an urging force while allowing movements of an interlocking member 9 and a pressure member 5 in a process where the interlocking member 9 moves and the pressure member 5 moves from the inactive position toward the active position.

Abstract: A torque damper apparatus includes an input-side plate having a pair of side plates and rotatably driven in response to drive force from a motor, a center plate coupled to an output shaft and arranged between the pair of side plates, and an elastic transmission body provided between the input-side plate and the center plate to transmit rotary drive force of the input-side plate to the center plate. The input-side plate has, at a plate surface of at least one side plate, multiple weight attachment holes for attaching a balance weight. Each weight attachment hole is formed in a long hole shape extending along a circumferential direction at an outer edge portion of the side plate.