Force coupling or torque coupling assemblies, apparatuses, systems, and methods include assemblies that each include superhard contact elements. At least some of the superhard contact elements may be configured to remain in contact with each other when a force is applied between the assemblies.

Force coupling or torque coupling assemblies, apparatuses, systems, and methods include assemblies that each include superhard contact elements. At least some of the superhard contact elements may be configured to remain in contact with each other when a rotational force and/or a thrust force is applied between the assemblies.

A driving force transmission mechanism is a mechanism for transmitting rotational force of the second rotor having a driving-side coupling to a first rotor having a driven-side coupling. The driving-side coupling includes a body and a plurality of second engaging members engaging with first engaging members of the driven-side coupling, each of the plurality of second engaging members has at an abutting point on an abutting surface of a corresponding first engaging member a first inclined surface inclined so as to be away from a rotation axis of the body from a downstream side toward an upstream side in a rotation direction of the body.

An electric power tool includes an electric motor with a motor gear, an output shaft with an input gear, a coupling that connects the motor gear to the input gear, and a housing that houses the motor, the motor gear, the coupling and the input gear. The coupling includes a shaft portion and two connective portions arranged at opposite ends of the shaft portion for connection to the motor gear and input gear, respectively. The motor gear and the input gear, each, have a cambered profile allowing a tilting movement of the coupling with respect to an axial position of one of the motor gear and the input gear that has a cambered profile.

A double-jointed coupling includes a carrier ring with an internal tooth arrangement, a hollow pinion shaft connected to the internal tooth arrangement of the carrier ring, and an intermediate shaft with a coupling tooth arrangement for engagement in the internal tooth arrangement. The coupling tooth arrangement is constructed on the intermediate shaft such as to enable passage of the intermediate shaft through the hollow pinion shaft for passage through the hollow pinion shaft. A thrust ring is arranged on the intermediate shaft in a region of the coupling tooth arrangement and constructed for passage through the hollow pinion shaft.

A torque transmission system having multiple torque transmission pathways from a driving shaft to a driven shaft. The driving shaft extends from a lower segment to an upper segment via an intermediate segment, the driven shaft extending from a first segment to a second segment. The transmission system includes a nominal spline coupling that is operational in a nominal operating mode, a backup spline coupling between the driving shaft and the driven shaft that is inactive in the nominal operating mode, and a backup radial guide device between the driving shaft and the driven shaft that is inactive in the nominal operating mode.

A coupling for allowing torque transmission between a first and second shaft, the coupling comprising: a cup-shaped portion provided at a first end of said first shaft and a first end of said second shaft being positioned within said cup-shaped portion; and said coupling further comprising a biasing means positioned between said first and second shafts, such that said biasing means is in contact with both of said first and second shafts. A shaft system can include the first coupling in combination with a third shaft and a second coupling that is provided between the third shaft and either a second end of said first shaft or a second end of said second shaft. The second coupling is identical to the first coupling.

The torque transmission joint includes an intermediate transmission member, and a first transmission member and a second transmission member that are arranged with one each on both side sections in the axial direction of the intermediate transmission member, with the outer side sections in the radial direction of each engaging with the inside section in the radial direction of the intermediate transmission member. The first transmission member and the second transmission member have a first preliminary engagement section and a second preliminary engagement section at the end sections in the axial direction on sides close to each other. The first preliminary engagement section and the second preliminary engagement section engage with each other with a circumferential gap interposed therebetween that does not disappear when torque transmission is performed between the first transmission member and the second transmission member via the intermediate transmission member.

A drive system 20, 20′ for rotating a wheel 11, 11′ of an aircraft landing gear 10, 10′, is disclosed having a drive element 24, 24′, a motor 21, 21′ operable to rotate the drive element, and a driven gear 25, 25′ adapted to be attached to the wheel. The drive system has a drive configuration in which the drive element is capable of meshing with the driven gear to drive the driven gear, wherein the drive system further comprises a transmission error measurement apparatus 30, 40, the apparatus configured to obtain, over time, measurement data of one or more characteristics of the drive system when in the drive configuration, the measurement data providing an indication of a transmission error between a torque commanded by the motor and a resulting torque at the driven gear. An aircraft 100 and a method of providing an indication of a transmission error in a drive system is disclosed.

A propeller shaft assembly for a vehicle including a first shaft extending along an axis between a proximal end and a distal end. The first shaft has an externally splined region presenting a plurality of external splines axially adjacent to the distal end. The externally splined region has a spline region outside diameter. A second shaft extends axially between a base end and a terminal end. The second shaft has a tube portion that extends from the base end, and an internally splined sleeve region that extends from the terminal end. The internally splined sleeve region receives the externally splined region of the first shaft and presents a plurality of internal splines interleaved with the external splines of the first shaft for providing relative axial movement between the first and second shafts while rotationally fixing the first and second shafts to one another. Components of the propeller shaft assembly have specific dimensional relationships to provide increased tool clearance, optimal bending stiffness, reduced mass and improved safety in vehicle crash situation.