Drive gear and driven gear
AssigneeEnplas Corporation
InventorsToru Hagihara, Shuhei Masuda
Life of this patent
Estimating the term…
Abstract
A gear reduction mechanism (1) includes a drive gear (10) having a rotation axis (L1), and a driven gear (20) driven in mesh with the drive gear (10) and having a rotation axis (L2) that is noncoplanar with the rotation axis (L1). The drive gear (10) is provided with spiral teeth, each having a tooth trace of a spiral curve having a spiral center on the rotation axis (L1) and a constant radial pitch, when viewed in the direction of the rotation axis (L1). Furthermore, the tooth profile of the driven gear (20) is set, considering a tangent angle that changes momentarily as the drive gear (10) rotates.
Claims7
A driven gear driven in mesh with a drive gear comprising spiral teeth, each having a tooth trace of a spiral curve having a spiral center on a rotation axis and a constant radial pitch, when viewed in a direction of the rotation axis, the driven gear having a rotation axis that is noncoplanar with the rotation axis of the drive gear, wherein the driven gear is a helical gear having a helix angle β within a range specified by
- γmin≤β≤γmax
- wherein γmin is an angle between a tangent line to the spiral curve of a spiral tooth at a maximum radius that is a radius at a point farthest from the rotation axis of the drive gear, and a line segment perpendicular to the maximum radius, and γmax is an angle between a tangent line to the spiral curve of a spiral tooth at a minimum radius that is a radius at a point closest to the rotation axis of the drive gear, and a line segment perpendicular to the minimum radius.
Dependencies are inferred from the claim text.