A method for designing a planetary gearset meeting one or more design targets is described. Initially, a size and ratio of the planetary gear set, and the number of planet gears for the planetary gearset is specified. All valid combinations of tooth numbers and planet numbers that satisfy one or more constraints are then calculated. From these, a starting combination is selected and a value for a design target for the gear set is calculated. One or more of the macro-geometry parameters are modified, and the macrogeometry parameters are chosen such that the positive effects of one macrogeometry parameter on the design target counteract any negative effects of another macrogeometry parameter. In this way, a design for planetary gearset meeting the one or more design targets is produced. Also disclosed is a method additionally calculating a sideband distribution resulting from the selected combination. The side band distribution is compared with a design target for sideband distribution and parameters are varied as necessary to achieve the required design.

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 vehicle drive device uses a parallel shaft gear reducer (30) in which a gear is composed of helical gear, as a speed reducer part (B) that decelerates and outputs a rotation of an electric motor part (A). In the vehicle drive device, of meshing parts of the gears formed in the speed reducer part (B), two gears form a meshing part in which the amount of misalignment that occurs between the tooth surfaces of the two gears meshing with each other is different during driving and during coasting of a vehicle. A first tooth surface (S1) meshing with a mating tooth surface during driving is subjected to tooth surface modification, and a second tooth surface (S2) meshing with a mating tooth surface during coasting is subjected to tooth surface modification of an amount different from an amount of the tooth surface modification to the first tooth surface (S1).

Methods of repairing a torque converter that enable the continued use of a torque converter and result in a repaired torque converter with a higher-strength and more durable construction. In some examples, a backing ring can be replaced with a replacement backing ring that includes a spline ring for replacing the function of a cover spline ring. In some examples, a method of repairing a torque converter can be improved by providing a replacement backing ring with a radial protrusion for locating the backing ring on the cover, and a method of determining an axial location of the radial protrusion.

A resin helical gear is formed by setting a first machining reference line obliquely coupling a tooth tip side of a first tooth to a tooth root side of a second tooth on another end side in the tooth width direction along a tooth surface, and a second machining reference line obliquely coupling a tooth tip side of the second tooth to a tooth root side of the first tooth along the tooth surface. Then, the tooth surface is cut out from the first machining reference line to the tooth root of the first tooth while the tooth surface is cut out from the second machining reference line to the tooth root of the second tooth. Then, an involute tooth profile form is left on a tooth tip side of the tooth with respect to the first machining reference line and the second machining reference line.

Gear pairing of a transmission with a first gear and with a second gear engaged with the first gear, whereby the first gear, in comparison to the second gear, is manufactured from a material that is less elastic or less soft, and whereby the first gear and the second gear have different normal target base pitches.

The invention concerns a spindle drive for the motorized adjustment of an adjusting element of a vehicle, comprising a drive motor with a motor shaft, a speed reduction gear mechanism, and a feed gear mechanism, the speed reduction gear mechanism having a planetary gear mechanism and the feed gear mechanism being designed as a spindle/spindle nut gear mechanism, the planetary gear mechanism having a rotatable sun gear and coaxially in relation thereto a rotatable planet-gear carrier and a fixed or fixable ring gear, and the planet-gear carrier carrying at least one rotatable planet gear, which is in axially parallel engagement with the sun gear on the one hand and the ring gear on the other hand, the drive motor, the speed reduction gear mechanism and the feed gear mechanism being accommodated one behind the other in a substantially elongate drive housing and aligned with a common longitudinal drive axis.

A gear drive device includes a first gear, a second gear that meshes with the first gear to allow torque transmission, and a biasing member that applies rotational torque in one direction to the first gear or the second gear. The first gear and the second gear are brought into contact at a contacting tooth surface thereof by the biasing member. At least one of the first gear and the second gear includes a non-contacting tooth surface that is on an opposite side of the contacting tooth surface and partially removed.

Methods of repairing a torque converter that enable the continued use of a torque converter and result in a repaired torque converter with a higher-strength and more durable construction. In some examples, a backing ring can be replaced with a replacement backing ring that includes a spline ring for replacing the function of a cover spline ring. In some examples, a method of repairing a torque converter can be improved by providing a replacement backing ring with a radial protrusion for locating the backing ring on the cover, and a method of determining an axial location of the radial protrusion.

A method for manufacturing a gear includes setting a function f(x) for forming a predetermined tooth profile in a gear, and forming a tooth root and tooth tip using function f(x). Function f(x) is defined so that: a surface shape of the tooth profile from the tooth root to tip has a vertex; a difference between a curvature radius of the surface shape at the tooth root and a radius of an arc or a radius of curvature of a parabola at the root is within a predetermined value; a difference between a curvature radius of the surface shape at the tooth tip and the arc radius or a curvature radius of the parabola at the tip is equal to or greater than a predetermined value; and the surface shape curvature radius at the tip becomes smaller than the arc radius or the parabola curvature radius at the tip.