A gear pairing for a helical gear unit or a spur gear unit, comprising a first gear with a first toothing portion, and a second gear with a second toothing portion, wherein the first gear has a first axis and the second gear has a second axis, which enclose a shaft angle, which is between 0 and 90°, the first toothing portion and the second toothing portion can be brought into meshing engagement and, when engaged, form an involute toothing, the materials of the first and second toothing portions are chosen so that, when engaged, a material pairing metal/plastic results, and the toothing portion made of plastic has a first helix angle and the toothing portion made of metal has a second helix angle.

A gear pairing for a helical gear unit or a spur gear unit, comprising a first gear with a first toothing portion, and a second gear with a second toothing portion, wherein the first gear has a first axis and the second gear has a second axis, which enclose a shaft angle, which is between 0 and 90°, the first toothing portion and the second toothing portion can be brought into meshing engagement and, when engaged, form an involute toothing, the materials of the first and second toothing portions are chosen so that, when engaged, a material pairing metal/plastic results, and the toothing portion made of plastic has a first helix angle and the toothing portion made of metal has a second helix angle.

A space and an elastic member have a first part where a distance between an outer peripheral surface of a metal bush and an inner peripheral surface of a resin member is a first distance, a second part where the distance between the outer peripheral surface and the inner peripheral surface is a second distance different from the first distance, and a third part where the distance between the outer peripheral surface and the inner peripheral surface is a third distance different from the first distance in a cross section along a radial direction of a resin gear. The first part is provided between the second part and the third part in an axial direction of the resin gear.

A space and an elastic member have a first part where a distance between an outer peripheral surface of a metal bush and an inner peripheral surface of a resin member is a first distance, a second part where the distance between the outer peripheral surface and the inner peripheral surface is a second distance different from the first distance, and a third part where the distance between the outer peripheral surface and the inner peripheral surface is a third distance different from the first distance in a cross section along a radial direction of a resin gear. The first part is provided between the second part and the third part in an axial direction of the resin gear.

A hollow reducer for high precision control includes a pin wheel housing and two-stage reduction components disposed in the pin wheel housing. A first-stage reduction component includes a driving wheel on a servo motor, a dual gear, and a planet wheel; and a second-stage reduction component includes 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, rigid disks, and bearings, wherein two eccentric sections of the eccentric shaft support the cycloidal gears by means of the bearings, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported on the left and right rigid disks by the bearings, and the rigid disks are supported on two sides of the pin wheel housing by the bearings.

A multi-piece gearwheel comprising an inner core section and an external toothed ring with external teething is presented. The core section has intermeshing teeth extending radially outwards, which have an undercut in cross-section in the radial direction. The toothed ring has recesses that originate from an inner side of the tooth ring and extend radially outwards, wherein the recesses are at least partially complementary to the intermeshing teeth, and wherein the intermeshing teeth are received in the recesses. Furthermore, a gearbox for an electromechanically-assisted steering system is described.

A multi-piece gearwheel comprising an inner core section and an external toothed ring with external teething is presented. The core section has intermeshing teeth extending radially outwards, which have an undercut in cross-section in the radial direction. The toothed ring has recesses that originate from an inner side of the tooth ring and extend radially outwards, wherein the recesses are at least partially complementary to the intermeshing teeth, and wherein the intermeshing teeth are received in the recesses. Furthermore, a gearbox for an electromechanically-assisted steering system is described.

Carbon fiber reinforced metal matrix composite gears include a planar carbon fiber structure fully encapsulated within a metal matrix formed of sintered metal nanoparticles. The metal nanoparticles can be composed of a metal having a high sintering temperature that would ordinarily destroy the carbon fiber. Novel techniques for making small uniform nanoparticles for sintering lowers the sintering temperature to a level that can accommodate carbon fiber. The composite gears possess high strength to weight ratio.

A gear of a speed reducer of an actuator includes: an insert component; a center portion; an outer peripheral portion; a connecting portion; a gate mark; a weld-line portion; and a rib-shaped portion. The center portion surrounds the insert component. The outer peripheral portion includes a toothed portion and a toothless portion. The weld-line portion is formed in at least one of the center portion, the connecting portion and the outer peripheral portion at a location which is on a radially inner side of the toothless portion. The rib-shaped portion is formed in at least one of the center portion, the connecting portion and the outer peripheral portion at a location which includes the weld-line portion. The rib-shaped portion has a wall thickness that is larger than a wall thickness of another circumferential portion.

A gear of a speed reducer of an actuator includes: an insert component; a center portion; an outer peripheral portion; a connecting portion; a gate mark; a weld-line portion; and a rib-shaped portion. The center portion surrounds the insert component. The outer peripheral portion includes a toothed portion and a toothless portion. The weld-line portion is formed in at least one of the center portion, the connecting portion and the outer peripheral portion at a location which is on a radially inner side of the toothless portion. The rib-shaped portion is formed in at least one of the center portion, the connecting portion and the outer peripheral portion at a location which includes the weld-line portion. The rib-shaped portion has a wall thickness that is larger than a wall thickness of another circumferential portion.