Injection molding resin gear and method of manufacturing the same
AssigneeCanon Kabushiki Kaisha
InventorKazunori Motoda
Life of this patent
Estimating the term…
Abstract
An injection molding resin gear includes: a tooth portion having teeth formed on an outer peripheral portion thereof; a shaft supporting portion formed around a center of rotation; and a web that connects the tooth portion and the shaft supporting portion, wherein the web includes a concave and convex portion having a concave portion formed on a first surface and a convex portion formed on a second surface formed at a position corresponding to the concave portion, and one of the concave portion or the convex portion of the concave and convex portion includes a gate point, and the concave and convex portions include a thinned portion at radial end portion in a radial cross section passing through the center of rotation of the concave and convex portion.
Claims9
An injection molding resin gear comprising:
- a tooth portion having teeth formed on an outer peripheral portion thereof;
- a shaft supporting portion formed around a center of rotation;
- and
- a web that connects the tooth portion and the shaft supporting portion, wherein
- the web includes a plurality of concave portions and a plurality of convex portions having a concave portion formed on a first surface and a convex portion formed on a second surface formed at a position corresponding to the concave portion, and one of the concave portions and the convex portions of the concave and convex portion includes a gate point, and the concave and convex portions include a thinned portion in a radial cross section passing through a center of rotation of the concave and convex portion.
A method of manufacturing an injection molding resin gear including:
- a tooth portion having teeth formed on an outer peripheral portion thereof;
- a shaft supporting portion formed around a center of rotation;
- and a web that connects the tooth portion and the shaft supporting portion, the method comprising:
- molding the injection molding resin gear by infusing a melted resin into a void defined when a first die and a second die are mated to each other by using the first die and the second die each including a teeth forming portion configured to transfer the tooth portion formed on the outer peripheral portion;
- transferring the shaft supporting portion formed around a center of rotation via a shaft supporting portion forming portion, and transferring the web that connects the tooth portion and the shaft supporting portion via a web forming portion, wherein
- the web forming portion is configured to transfer the web including a die concave and convex having a die concave formed on the first die, and a die convex formed on the second die formed at a position corresponding to the die concave when the first die and the second die are mated to each other, and infusing the melted resin from a gate arranged at the die concave or the die convex.
Dependencies are inferred from the claim text.