A drive device includes: a motor; and a power transmission device that transmits power of the motor to a wheel. Further, in the power transmission device has a meshing portion in which a meshing tooth that is formed on an input-side rotation member and a meshing tooth that is formed on an output-side rotation member mesh with each other on a power transmission path between the motor and the wheel, the meshing tooth has a driving-side teeth surface that makes contact for transmission of power from the motor to the wheel and a non-driving-side teeth surface that makes contact for transmission of power from the wheel to the motor, and in the meshing tooth, a tooth root of the driving-side teeth surface has a higher breaking strength than a tooth root of the non-driving-side teeth surface.

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 harmonic speed reducer is provided. The harmonic speed reducer includes a wave generator, a flexible gear, a first rigid gear, and a second rigid gear. The wave generator can be driven to rotate relative to a central axis. The flexible gear has a plurality of first outer gear structures, a division groove, and a plurality of second outer gear structures. The first rigid gear has a plurality of first inner gear structures configured to be engaged with the first outer gear structures. The second rigid gear has a plurality of second inner gear structures configured to be engaged with the second outer gear structures. A first intersection line is defined between each of the first inner gear structures and a sectional surface. An angle between the first intersection line and a first horizontal line is within a range from 0.1 degrees to 5 degrees.

A bearing including a bearing ring having an annular base and a plurality of gear teeth integrally formed with the annular base. Each gear tooth of the plurality of gear teeth includes a first flank surface extending substantially radially from the annular base, a top land surface extending substantially in the axial direction, and a chamfered surface between the top land surface and first flank surface. The chamfered surface includes a first arc with a first radius in a range of 0.1 to 0.15 times the gear module of the bearing ring. The first arc has a point of tangency with the first flank surface. The chamfered surface has length P extending in the radial direction between the point of tangency and the top land surface, and P is in the range of 0.1 to 0.15 times the gear module of the bearing ring.

A reducer for high precision control includes a pin gear housing and two-stage reduction components disposed therein: a first-stage reduction component including an input shaft, a sun gear and a planet gear; and a second-stage reduction component including 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, a left rigid disk and a right rigid disk, and bearings, wherein the cycloidal gears are supported by bearings on two eccentric sections of the eccentric shaft, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported by bearings on the left rigid disk and the right rigid disk, and the left rigid disk and the right rigid disk are supported by bearings in inner holes of two sides of the pin gear housing.

A method of manufacturing a gear is provided. The method includes forming a plurality of gear teeth in a surface of a gear, the gear teeth having tooth faces defining tooth edges including tooth edge flanks and tooth edge top land and generating a convex contour at an edge break of at least one of the tooth edge flanks and tooth edge top land.

A bevel gear set and a method of manufacturing the same are provided. The bevel gear set may include a first bevel gear and a second bevel gear. The first and second bevel gears may be spiral bevel gears or hypoid spiral bevel gears. The first and second bevel gears may each have a gear tooth surface having a plurality of teeth formed thereon, such that the teeth of the first bevel gear and the teeth of the second bevel gear are configured to engage in a meshing engagement. The teeth are machined onto the respective gear tooth surface via a face milling process. Each tooth includes a tooth top, a plurality of meshing surfaces, and at least one chamfer. The chamfer may be formed at an abutment edge disposed between the tooth top and a respective meshing surface via a brushing process directly following the machining of the teeth.

A harmonic speed reducer is provided. The harmonic speed reducer includes a wave generator, a flexible gear, a first rigid gear, and a second rigid gear. The wave generator can be driven to rotate relative to a central axis. The flexible gear has a plurality of first outer gear structures, a division groove, and a plurality of second outer gear structures. The first rigid gear has a plurality of first inner gear structures configured to be engaged with the first outer gear structures. The second rigid gear has a plurality of second inner gear structures configured to be engaged with the second outer gear structures. A first intersection line is defined between each of the first inner gear structures and a sectional surface. An angle between the first intersection line and a first horizontal line is within a range from 0.1 degrees to 5 degrees.

A reducer for high precision control includes a pin gear housing and two-stage reduction components disposed therein: a first-stage reduction component including an input shaft, a sun gear and a planet gear; and a second-stage reduction component including 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, a left rigid disk and a right rigid disk, and bearings, wherein the cycloidal gears are supported by bearings on two eccentric sections of the eccentric shaft, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported by bearings on the left rigid disk and the right rigid disk, and the left rigid disk and the right rigid disk are supported by bearings in inner holes of two sides of the pin gear housing.

A drive device includes: a motor; and a power transmission device that transmits power of the motor to a wheel. Further, in the power transmission device has a meshing portion in which a meshing tooth that is formed on an input-side rotation member and a meshing tooth that is formed on an output-side rotation member mesh with each other on a power transmission path between the motor and the wheel, the meshing tooth has a driving-side teeth surface that makes contact for transmission of power from the motor to the wheel and a non-driving-side teeth surface that makes contact for transmission of power from the wheel to the motor, and in the meshing tooth, a tooth root of the driving-side teeth surface has a higher breaking strength than a tooth root of the non-driving-side teeth surface.