Abstract: A piezoelectric vibration element includes a piezoelectric piece having a main surface; an excitation electrode disposed on the main surface of the piezoelectric piece; and a connection electrode disposed on the main surface of the piezoelectric piece and electrically connected to the excitation electrode, wherein when the main surface of the piezoelectric piece is viewed in a plan, the piezoelectric piece has a through-hole in an area between the excitation electrode and the connection electrode, and wherein an internal wall of the through-hole located closer to the excitation electrode has at least four slopes.

Abstract: An automatic transmission is provided, which includes a transmission case having a vertical wall part, a clutch disposed on a first side of the vertical wall part in an axial direction, a given component disposed on the second side of the vertical wall part, and a sleeve having a cylindrical body and a flange part coupled to the second side of the vertical wall part and disposed radially inward of the given component. The hydraulic fluid is supplied to the clutch from radially inward of the clutch through the vertical wall part. An oil supply passage is configured to supply the hydraulic fluid to the radially inward of the clutch through a first oil passage extending in the axial direction via a coupling part between the vertical wall part and the flange part, a second oil passage inside the flange part, and a third oil passage inside the cylindrical body.

Abstract: An automatic transmission with a brake is provided, the brake including a hub member coupled to a transmission case. The hub member includes a first hub member having a cylindrical part spline-engaged with friction plates and the transmission case, and forming a disengagement hydraulic chamber, a second hub member disposed at one side of the first hub member in the axial direction, fitted into the transmission case, and coupled to the one side of the first hub member in the axial direction by a first coupling member, and a third hub member disposed at the other side of the first hub member in the axial direction, coupled to the other side of the first hub member in the axial direction by a second coupling member, and forming an engagement hydraulic chamber. The first coupling member and the second coupling member are disposed radially inward of the disengagement hydraulic chamber.

Abstract: An automatic transmission is provided, which includes a transmission case having a vertical wall part, a clutch disposed on a first side of the vertical wall part in an axial direction, a given component disposed on the second side of the vertical wall part, and a sleeve having a cylindrical body and a flange part coupled to the second side of the vertical wall part and disposed radially inward of the given component. The hydraulic fluid is supplied to the clutch from radially inward of the clutch through the vertical wall part. An oil supply passage is configured to supply the hydraulic fluid to the radially inward of the clutch through a first oil passage extending in the axial direction via a coupling part between the vertical wall part and the flange part, a second oil passage inside the flange part, and a third oil passage inside the cylindrical body.

Abstract: An automatic transmission with a brake is provided, the brake including a hub member coupled to a transmission case. The hub member includes a first hub member having a cylindrical part spline-engaged with friction plates and the transmission case, and forming a disengagement hydraulic chamber, a second hub member disposed at one side of the first hub member in the axial direction, fitted into the transmission case, and coupled to the one side of the first hub member in the axial direction by a first coupling member, and a third hub member disposed at the other side of the first hub member in the axial direction, coupled to the other side of the first hub member in the axial direction by a second coupling member, and forming an engagement hydraulic chamber. The first coupling member and the second coupling member are disposed radially inward of the disengagement hydraulic chamber.

Abstract: A frictional engagement element includes: a first piston, a second piston, a first urging member for urging the first piston in a direction of releasing a friction plate, and a second urging member for urging the second piston in the direction of releasing the friction plate with an urging force larger than the urging force of the first urging member. One of the first and second pistons has a communicating hole for connecting an engaging hydraulic chamber with an opposite hydraulic chamber and the other of the first and second pistons has a valve part for closing the communicating hole. The difference in travel distance between the first and second pistons in motion due to the different urging forces of the first and second urging members causes the valve part to open the communicating hole.

Abstract: An automatic transmission includes a piston movable in an axial direction, a plurality of friction plates disposed on a side of a first surface of the piston, a fastening hydraulic chamber applying a hydraulic pressure to a second surface of the piston to move the piston to a fastening position where the friction plates are pressed to be fastened to each other, a release hydraulic chamber applying a hydraulic pressure to the first surface of the piston to move the piston to a release position where the friction plates are released, and a hydraulic pressure control valve that supplies and discharges the hydraulic pressure to and from each of the fastening hydraulic chamber and the release hydraulic chamber. An area of the second surface of the piston for receiving the hydraulic pressure is set to be larger than an area of the first surface for receiving the hydraulic pressure.

Abstract: In a brake device of a transmission, rotation side friction plates are engaged with a cylindrical part of a rotation side holding member, and fixed side friction plates are engaged with a spline part that is provided on an outer peripheral surface of an inner cylindrical part of a fixed side holding member opposed to a cylindrical part of the rotation side holding member. The fixed side holding member includes an inflow oil passage that supplies lubricating oil from the outside to the inside of the radial direction thereof. An annular space communicating with an inflow oil passage is provided on the inside of the cylindrical part of the fixed side holding member. Oil discharge holes supplying lubricating oil, which was flowed into the annular space, to the rotation side and fixed side friction plates are provided on the cylindrical part of the fixed side holding member.

Abstract: A power transmission apparatus with a centrifugal pendulum damper is realized, which can effectively suppress torque fluctuation and vibration noise of a vehicle while avoiding size increase of a centrifugal pendulum damper and deterioration of reliability of the centrifugal pendulum damper by high-speed rotation. A power transmission apparatus with a centrifugal pendulum damper includes: a centrifugal pendulum damper coupled to an input shaft through a speed-increasing mechanism configured to increase speed of rotation of the input shaft; and an engagement/disengagement mechanism capable of realizing and cutting off power transmission from the input shaft to the centrifugal pendulum damper.

Abstract: A frictional engagement element includes: a first piston, a second piston, a first urging member for urging the first piston in a direction of releasing a friction plate, and a second urging member for urging the second piston in the direction of releasing the friction plate with an urging force larger than the urging force of the first urging member. One of the first and second pistons has a communicating hole for connecting an engaging hydraulic chamber with an opposite hydraulic chamber and the other of the first and second pistons has a valve part for closing the communicating hole. The difference in travel distance between the first and second pistons in motion due to the different urging forces of the first and second urging members causes the valve part to open the communicating hole.

Abstract: In a brake device of a transmission, rotation side friction plates are engaged with a cylindrical part of a rotation side holding member, and fixed side friction plates are engaged with a spline part that is provided on an outer peripheral surface of an inner cylindrical part of a fixed side holding member opposed to a cylindrical part of the rotation side holding member. The fixed side holding member includes an inflow oil passage that supplies lubricating oil from the outside to the inside of the radial direction thereof. An annular space communicating with an inflow oil passage is provided on the inside of the cylindrical part of the fixed side holding member. Oil discharge holes supplying lubricating oil, which was flowed into the annular space, to the rotation side and fixed side friction plates are provided on the cylindrical part of the fixed side holding member.

Abstract: A power transmission apparatus with a centrifugal pendulum damper is realized, which can effectively suppress torque fluctuation and vibration noise of a vehicle while avoiding size increase of a centrifugal pendulum damper and deterioration of reliability of the centrifugal pendulum damper by high-speed rotation. A power transmission apparatus with a centrifugal pendulum damper includes: a centrifugal pendulum damper coupled to an input shaft through a speed-increasing mechanism configured to increase speed of rotation of the input shaft; and an engagement/disengagement mechanism capable of realizing and cutting off power transmission from the input shaft to the centrifugal pendulum damper.

Abstract: An automatic transmission includes a piston movable in an axial direction, a plurality of friction plates disposed on a side of a first surface of the piston, a fastening hydraulic chamber applying a hydraulic pressure to a second surface of the piston to move the piston to a fastening position where the friction plates are pressed to be fastened to each other, a release hydraulic chamber applying a hydraulic pressure to the first surface of the piston to move the piston to a release position where the friction plates are released, and a hydraulic pressure control valve that supplies and discharges the hydraulic pressure to and from each of the fastening hydraulic chamber and the release hydraulic chamber. An area of the second surface of the piston for receiving the hydraulic pressure is set to be larger than an area of the first surface for receiving the hydraulic pressure.

Abstract: Provided is a torque converter (1) which comprises: a casing (10) coupled to an output shaft of an engine; a torus (T) defined by a pump (20), a turbine (30) and a stator (40) each disposed within the casing (10); a multi-plate lockup clutch (60) adapted to directly couple the turbine (30) and the casing (10); and a lockup damper (70) adapted to absorb shock during engagement of the lockup clutch (60). The lockup clutch (60) and the lockup damper (70) are arranged within a space between the torus (T) and a surface of the casing (10) on the side of the engine, in an axially overlapping relation. The lockup clutch (60) is disposed on a radially inner side with respect to a widest region (T1) of the torus (T), and the lockup damper (70) is disposed on a radially outer side with respect to the widest region (T1). This makes it possible to engage the lockup clutch (60) with excellent response while suppressing shock, and shorten an overall length of an automatic transmission.

Abstract: A torque converter includes, in a case coupled to an output shaft of an engine, a torus formed from a pump, a turbine and a stator having a one-way clutch on the inside thereof, and a lock-up clutch. In addition, in this torque converter, a fluid from a pump is introduced from a space between a stator shaft (F2) and a turbine shaft (F1), and discharged from a space between a pump sleeve (23) and the stator shaft (F2) through a space where the lock-up clutch is disposed and the torus. Moreover, this torque converter further includes a seal member (80) which is disposed at a side that is closer to the engine than a spline engagement part (P2) of an inner race (52) and the stator shaft (F2), and seals a space between an inner peripheral face of the inner race (52) and an outer peripheral face of the stator shaft (F2).

Abstract: Disclosed is a torque converter (1) which comprises: a casing (10) coupled to an output shaft of an engine; a torus (T) defined by a pump (20), a turbine (30) and a stator (40) each disposed within the casing (10); a lockup clutch (60) adapted to directly couple the turbine (30) and the casing (10); and a lockup damper (70) adapted to absorb shock during engagement of the lockup clutch (60). The turbine (30) has an outer peripheral portion (31a) bulging toward the engine to define a part of the torus (T), an inner peripheral portion (31c) located on the side of the engine with respect to a one-way clutch (50) supporting the stator (40), and an intermediate portion (31b) formed to be concaved toward a side opposite to the engine, in a radial position between the outer peripheral portion (31a) and the inner peripheral portion (31c). A part (75) of the lockup damper (70) is disposed on the side of the engine with respect to the intermediate portion (31b) and in a position axially overlapping with the torus (T).

Abstract: A torque converter includes, in a case coupled to an output shaft of an engine, a torus formed from a pump, a turbine and a stator having a one-way clutch on the inside thereof, and a lock-up clutch. In addition, in this torque converter, a fluid from a pump is introduced from a space between a stator shaft (F2) and a turbine shaft (F1), and discharged from a space between a pump sleeve (23) and the stator shaft (F2) through a space where the lock-up clutch is disposed and the torus. Moreover, this torque converter further includes a seal member (80) which is disposed at a side that is closer to the engine than a spline engagement part (P2) of an inner race (52) and the stator shaft (F2), and seals a space between an inner peripheral face of the inner race (52) and an outer peripheral face of the stator shaft (F2).

Abstract: Disclosed is a torque converter (1) which comprises: a casing (10) coupled to an output shaft of an engine; a torus (T) defined by a pump (20), a turbine (30) and a stator (40) each disposed within the casing (10); a lockup clutch (60) adapted to directly couple the turbine (30) and the casing (10); and a lockup damper (70) adapted to absorb shock during engagement of the lockup clutch (60). The turbine (30) has an outer peripheral portion (31a) bulging toward the engine to define a part of the torus (T), an inner peripheral portion (31c) located on the side of the engine with respect to a one-way clutch (50) supporting the stator (40), and an intermediate portion (31b) formed to be concaved toward a side opposite to the engine, in a radial position between the outer peripheral portion (31a) and the inner peripheral portion (31c). A part (75) of the lockup damper (70) is disposed on the side of the engine with respect to the intermediate portion (31b) and in a position axially overlapping with the torus (T).

Abstract: Provided is a torque converter (1) which comprises: a casing (10) coupled to an output shaft of an engine; a torus (T) defined by a pump (20), a turbine (30) and a stator (40) each disposed within the casing (10); a multi-plate lockup clutch (60) adapted to directly couple the turbine (30) and the casing (10); and a lockup damper (70) adapted to absorb shock during engagement of the lockup clutch (60). The lockup clutch (60) and the lockup damper (70) are arranged within a space between the torus (T) and a surface of the casing (10) on the side of the engine, in an axially overlapping relation. The lockup clutch (60) is disposed on a radially inner side with respect to a widest region (T1) of the torus (T), and the lockup damper (70) is disposed on a radially outer side with respect to the widest region (T1). This makes it possible to engage the lockup clutch (60) with excellent response while suppressing shock, and shorten an overall length of an automatic transmission.

Abstract: An automatic transmission has first, second and third gear sets, first and second clutches, and first, second and third brakes. First, second and third sun gears, and a first carrier are interconnected with a second sun gear, a second carrier, a third carrier, an input shaft and an output gear, respectively. The first clutch selectively connects the first sun gear and the second sun gear to the input shaft, and the second clutch selectively connects the first ring gear and the second carrier to the input shaft. The first brake selectively connects the first ring gear and the second carrier to a casing. The second brake selectively connects the second ring gear and the third carrier to the casing, and the third brake selectively connects the third ring gear to the casing.