A method and system are provided for shifting a vehicle transmission having several members. Each member is a first, second, or third node of a planetary gear set (of multiple planetary gear sets), or an input, output, or stationary member. A first torque transmitting mechanism is applied to transfer torque between first and second members in a low gear state. In some versions, a second torque transmitting mechanism is applied in the low gear state without substantially transferring torque between third and fourth members, and then the second torque transmitting mechanism is disengaged. A third torque transmitting mechanism is then applied without substantially transferring torque between the third and fourth members in the low gear state. The transmission is upshifted by disengaging the first torque transmitting mechanism, keeping the third torque transmitting mechanism applied, and applying the second torque transmitting mechanism to transfer torque between the third and fourth members.

A method of operating a transmission which is shifted to various operating conditions by engaging shifting elements. At least one of the shifting elements is an interlocking shifting element which has to be engaged to obtain at least one defined operating condition of the transmission during which force flows between an input and an output shaft. When a command is received to engage the interlocking shifting element, a rotational speed of the transmission input shaft is displaced in the direction toward a synchronous rotational speed produced in the engaged operating condition of the interlocking shifting element at least as a function of the rotational speed of the transmission output shaft. When the variation of the rotational speed of the transmission input shaft crosses a predefined rotational speed threshold, the interlocking shifting element is actuated in its engaging direction.

An automatic transmission is provided. The transmission includes clutches coaxially arranged in layers in a radial direction of the transmission. The transmission includes a piston provided to each clutch, the pistons being aligned in the radial direction on a same plane perpendicular to an axis of the transmission, without overlapping with each other in an axial view. The transmission includes a common rotational member having a wall, commonly used for the clutches, and disposed at a predetermined position of the transmission in an axial direction, wherein the wall is formed along the plane. The transmission includes operational hydraulic passages parallely arranged in the wall of the common rotational member in a circumferential direction of the transmission on the same plane perpendicular to the axis, each of the operational hydraulic passages communicating with one of operational hydraulic chambers of the respective clutches.

An automatic transmission is provided. The transmission includes clutches coaxially arranged in layers in a radial direction of the transmission. The transmission includes a piston provided to each clutch, the pistons being aligned in the radial direction on a same plane perpendicular to an axis of the transmission, without overlapping with each other in an axial view. The transmission includes a common rotational member having a wall, commonly used for the clutches, and disposed at a predetermined position of the transmission in an axial direction, wherein the wall is formed along the plane. The transmission includes operational hydraulic passages parallely arranged in the wall of the common rotational member in a circumferential direction of the transmission on the same plane perpendicular to the axis, each of the operational hydraulic passages communicating with one of operational hydraulic chambers of the respective clutches.

A drive transmission device includes a clutch mechanism. The clutch mechanism includes a drive transmission member that is coupled to a first rotation member via a torque limiter and is arranged in a fitting part of a second rotation member and a third rotation member, and a transmission member moving part that includes a first gap and a second gap, the first gap being formed in the fitting part and having a width wider than the thickness of the drive transmission member and the second gap being formed in the fitting part and having a width that is equal to or smaller than the thickness of the drive transmission member, the transmission member moving part being formed in such a way that the width thereof becomes smaller about a rotation axis in the fitting part.

A power tool includes an output shaft for outputting torque, a motor for driving the output shaft to rotate about a first axis, a transmission mechanism for transmitting an output of the motor to the output shaft, a gear box for containing the transmission mechanism, a sleeve for a user to operate so as to adjust a maximum output torque transmitted from the motor to the output shaft, a locating element for limiting an axial position of the sleeve, fastening elements for fixing the locating element to the gear box, and a bearing for supporting the output shaft. The locating element is formed with a containing groove for containing the bearing and locating holes formed on a bottom of the containing groove. The fastening elements are at least partially embedded in the locating holes.

A power tool includes an output shaft for outputting torque, a motor for driving the output shaft to rotate about a first axis, a transmission mechanism for transmitting an output of the motor to the output shaft, a gear box for containing the transmission mechanism, a sleeve for a user to operate so as to adjust a maximum output torque transmitted from the motor to the output shaft, a locating element for limiting an axial position of the sleeve, fastening elements for fixing the locating element to the gear box, and a bearing for supporting the output shaft. The locating element is formed with a containing groove for containing the bearing and locating holes formed on a bottom of the containing groove. The fastening elements are at least partially embedded in the locating holes.

An electric work machine includes: a motor; a first planetary gear mechanism; a second planetary gear mechanism; a spindle; a first speed switch mechanism including a first internal gear of a first stage unit and a second internal gear of a second stage unit; and a second speed switch mechanism. The first speed switch mechanism performs switching between a first speed reducing mode in which rotation of the second internal gear is prevented and rotation of the first internal gear is allowed and a second speed reducing mode in which rotation of the first internal gear is prevented and rotation of the second internal gear is allowed. The second speed switch mechanism performs switching between an enabled mode in which rotation of an internal gear of the second planetary gear mechanism is prevented and a disabled mode in which the rotation of the internal gear is allowed.

A power shift transmission includes a plurality of shafts, a plurality of gears, a plurality of clutches, a plurality of forward modes, and a plurality of alternate forward modes. Each forward mode has a distinct transmission ratio, and each alternate forward mode has a transmission ratio similar to one of the plurality of forward modes.

An emergency steering system for a vehicle, may include a planetary gear mounted in an inlet space of a gear box for a steering apparatus so that the planetary gear is ordinarily operated at a gear ratio of 1:1 and has an increased gear ratio in the event of failure of a main steering device; and a gear ratio increasing device mounted to an upper plate portion of the gear box to increase the gear ratio of the planetary gear.