Motor having deceleration mechanism
AssigneeMitsuba Corporation
InventorsHiroyuki Uchimura, Kazuaki Aoki
Life of this patent
Estimating the term…
Abstract
Because the pressure angle β° (=12°) of teeth (47) of a worm wheel (46) is larger than the pressure angle α° (=11°) of teeth (45) of a worm (44), tips of the teeth (47) of the worm wheel (46) can be more tapered as compared with a case in which the pressure angle of the teeth of the worm and the pressure angle of the teeth of the worm wheel are the same angle (the conventional case). Thereby, it is possible to ensure non-contact of teeth, which had been variable in terms of contact and non-contact in the case of the conventional form, even if there has been non-uniformity in the teeth (47) of the worm wheel (46).
Claims5
A motor having deceleration mechanism which decelerates and outputs rotation of an armature shaft, comprising:
- a worm rotated by the armature shaft, and
- a worm wheel engaged with the worm;
- wherein a first angle of a teeth of the worm wheel is larger than a second angle of a teeth of the worm,
- wherein the second angle of the teeth of the worm is defined as an angle formed between a first reference line and a first tangent line, the first reference line is orthogonal to a pitch circle diameter of the worm and extends from a first pitch point on the pitch circle diameter of the worm and extends away from the worm, the first pitch point is located on a surface of the teeth of the worm, the first tangent line extends from the first pitch point on the pitch circle diameter of the worm and extends away from the worm, the first tangent line is tangent to the surface of the teeth of the worm, the second angle of the teeth of the worm is an acute angle,
- wherein the first angle of the teeth of the worm wheel is defined as an angle formed between a second reference line and a second tangent line, the second reference line is orthogonal to a pitch circle diameter of the worm wheel and extends from a second pitch point on the pitch circle diameter of the worm wheel and extends away from the worm wheel, the second pitch point is located on a surface of the teeth of the worm wheel, the second tangent line extends from the second pitch point on the pitch circle diameter of the worm wheel and extends away from the worm wheel, the second tangent line is tangent to a surface of the teeth of the worm wheel, the first angle of the teeth of the worm wheel is an acute angle.
Dependencies are inferred from the claim text.