A downsized differential assembly having a simple structure, which can be mounted easily on automobiles. The differential assembly comprises: a first gear as an internal gear; a second gear as an external gear; a first eccentric gear as an external gear meshed with the first gear; a second eccentric gear as an internal gear meshed with the second gear; a supporting member supporting the first eccentric gear and the second eccentric gear; a first motion translating mechanism translating revolving motion of the first eccentric gear into rotary motion of the first rotary shaft; and a second motion translating mechanism translating revolving motion of the second eccentric gear into rotary motion of the second rotary shaft. Gear ratios between the first gear and the first eccentric gear and between the second gear and the second eccentric gear are different, and the first rotary shaft and the second rotary shaft are rotated in opposite directions.

A downsized differential assembly having a simple structure, which can be mounted easily on automobiles. The differential assembly comprises: a first gear as an internal gear; a second gear as an external gear; a first eccentric gear as an external gear meshed with the first gear; a second eccentric gear as an internal gear meshed with the second gear; a supporting member supporting the first eccentric gear and the second eccentric gear; a first motion translating mechanism translating revolving motion of the first eccentric gear into rotary motion of the first rotary shaft; and a second motion translating mechanism translating revolving motion of the second eccentric gear into rotary motion of the second rotary shaft. Gear ratios between the first gear and the first eccentric gear and between the second gear and the second eccentric gear are different, and the first rotary shaft and the second rotary shaft are rotated in opposite directions.

A multi-axis rotary actuator includes a payload support configured to be rotatable about a first axis, a disk surrounding at least a portion of the payload support, and an elevation wheel rotatably coupled to the payload support. The disk is configured to be rotatable about the first axis. The elevation wheel is configured to be in contact with the disk and to be rotatable about a second axis perpendicular to the first axis. The actuator can include a mirror or other device coupled to the elevation wheel. The mirror or other device is configured to be rotatable about the first axis and the second axis as the payload support and the elevation wheel rotate about the first axis and the second axis, respectively.

A differential with a washer for a gear in a differential housing includes an outer edge at a maximum radial distance from an axis, and an inner edge defining an opening, the inner edge defined in part by an innermost portion at a minimum radial distance from the axis and the inner edge having an outward portion spaced radially outwardly from the innermost portion. The washer also includes an axially and radially inclined sidewall extending at least part of the way between the outer edge and the innermost portion.

A differential with a washer for a gear in a differential housing includes an outer edge at a maximum radial distance from an axis, and an inner edge defining an opening, the inner edge defined in part by an innermost portion at a minimum radial distance from the axis and the inner edge having an outward portion spaced radially outwardly from the innermost portion. The washer also includes an axially and radially inclined sidewall extending at least part of the way between the outer edge and the innermost portion.

A differential reducer for a motor vehicle, including: a differential mechanism including a ring gear; a reduction mechanism including a secondary pinion and a primary pinion; a crankcase including a first half-crankcase and a second half-crankcase, of which an internal transverse wall of each half includes three bearing seats, each internal transverse wall having first means for collecting and directing oil sprayed by the ring gear, which means turn in a first direction of rotation to the bearing seats; wherein each internal wall includes second means for collecting oil which is sprayed substantially transversally through rotation of the ring gear in a second direction of rotation.

A differential reducer for a motor vehicle, including: a differential mechanism including a ring gear; a reduction mechanism including a secondary pinion and a primary pinion; a crankcase including a first half-crankcase and a second half-crankcase, of which an internal transverse wall of each half includes three bearing seats, each internal transverse wall having first means for collecting and directing oil sprayed by the ring gear, which means turn in a first direction of rotation to the bearing seats; wherein each internal wall includes second means for collecting oil which is sprayed substantially transversally through rotation of the ring gear in a second direction of rotation.

A method for forming an assembly having a housing and first and second components. The first and second components are movable relative to one another in the housing. The method includes: providing first and second workpieces; moving the first and second workpieces relative to one another in a predetermined manner that produces relative sliding contact between the first and second workpieces while performing a superfinishing operation on the first and second workpieces to form the first and second components, respectively, wherein the superfinishing operation does not comprise a lapping operation; and mounting the first and second components in the housing such that the first and second components are engaged to one another and are movable relative to one another in the predetermined manner.

A method for forming an assembly having a housing and first and second components. The first and second components are movable relative to one another in the housing. The method includes: providing first and second workpieces; moving the first and second workpieces relative to one another in a predetermined manner that produces relative sliding contact between the first and second workpieces while performing a superfinishing operation on the first and second workpieces to form the first and second components, respectively, wherein the superfinishing operation does not comprise a lapping operation; and mounting the first and second components in the housing such that the first and second components are engaged to one another and are movable relative to one another in the predetermined manner.

A power train for a vehicle may include a differential case; a differential ring gear aligned to be concentric to the differential case, and provided in a relatively rotatable state therebetween; and a connection/disconnection mechanism provided to connect or disconnect the differential ring gear and the differential case in a state where power is transferred thereto.