Bevel gear
AssigneeNissan Motor Co., Ltd.
InventorsHiroshi Takano, Yujiro Ohara, Hiroshi Yamashita, Atsushi Hayata
Life of this patent
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Abstract
A bevel gear 1 has a radius of curvature R of a fillet curve provided between a tooth flank A and a bottom land B gradually increasing from a small-diameter end D1 to a large-diameter end D2.
Claims9
A bevel gear comprising a plurality of teeth each having a tooth flank, the tooth flank being connected with a bottom land via a fillet curve having a radius of curvature, and a large-diameter end and a small-diameter end, wherein the radius of curvature of the fillet curve at the large-diameter end is greater than the radius of curvature at the small-diameter end, wherein a maximum radius of curvature of the fillet curve is equal in value to the difference between a minimum meshing circle radius with respect to a mating gear and a dedendum circle radius.
A bevel gear according to 1, wherein the radius of curvature of the fillet curve between the tooth flank and the bottom land gradually increases from the small-diameter end to the large-diameter end.
A bevel gear according to 1, further comprising a web provided at the outer edge of the bottom land, extending between the opposing tooth flanks.
A bevel gear according to 1, wherein:
- the small-diameter end is shaped to have two different radii of curvature;
- and
- the large-diameter end is shaped to have a single radius of curvature.
A bevel gear according to 1, wherein a boundary portion between the tooth flank and an outer surface of the tooth is shaped to have a radius of curvature.
A bevel gear according to 1, prepared by a process comprising:
- preparing a forging die with a gear mold in a reversed shape of the bevel gear;
- and
- forging the bevel gear with the forging die.
A bevel gear according to 6, prepared by a process further comprising:
- preparing an electrode for electric discharge machining having a shape similar to that of the bevel gear;
- and
- producing a forging die with a gear mold in a reversed shape of the bevel gear, using the electrode.
A bevel gear according to 7, wherein the electrode for electric discharge machining is provided with a cylinder extending coaxially with a radius substantially identical to that of the large-diameter end.
A bevel gear comprising a plurality of teeth each having a tooth flank, the tooth flank being connected with a bottom land via a fillet curve having a radius of curvature, and a large-diameter end and a small-diameter end, wherein the radius of curvature of the fillet curve at the large-diameter end is greater than the radius of curvature at the small-diameter end, and further comprising a web provided at the outer edge of the bottom land, extending between the opposing tooth flanks wherein a boundary portion between the tooth flank and the web is shaped to have curvature with a radius of curvature equal to the radius of curvature of the large-diameter end.
Dependencies are inferred from the claim text.