JP2016093910A5 - Gear, gear manufacturing method, copying machine, and printer - Google Patents

Claims (7)

A tooth portion having teeth formed on the outer periphery of an annular rim, a shaft portion formed at a center portion, and a plurality of connection portions connecting the tooth portions and the shaft portion; A gear having at least one tooth region having a different number of teeth when the tooth portion is divided into a plurality of tooth region by a center line;
The angle formed between the tangent line of the inner periphery of the tooth part and the center line at the point where the center line of at least one of the plurality of connection parts contacts the inner periphery of the tooth part is:
A gear having a larger tooth portion region side of the tooth portion regions adjacent to each other with the at least one connection portion interposed therebetween is smaller.   The gear according to claim 1, wherein the connection portion is formed at three positions.   The difference in angle between the point where the center line of the three connecting portions in contact with the inner periphery of the tooth part contacts the inner periphery of the tooth part and the line connecting the center O of the gear is 6 ° or more. The gear according to claim 1, wherein the gear is smaller than 45 °. A tooth portion formed by a rim formed on the outer periphery and formed on the back side of the tooth, a shaft portion formed in a central portion, and a plurality of connection portions connecting the tooth portion and the shaft portion; When the tooth part is divided into a plurality of tooth part regions by a plurality of connecting parts, a manufacturing method of a gear having at least one tooth part region having a different size,
A cavity having a space for forming the tooth portion, a space for forming the shaft portion, and a space for forming the plurality of connection portions,
Injecting resin from each of the spaces for molding the plurality of connecting portions,
The at least one tooth region having a different size and the adjacent tooth region have at least one tooth region having a different size and a larger tooth region among the adjacent tooth regions. A gear manufacturing method, wherein a resin is injected into a space for forming the tooth portion from a space for forming the one connecting portion that is inclined.   The gear manufacturing method according to claim 4, wherein the resin is a resin containing any one of polyacetal, polybutylene terephthalate, polyphenylene sulfide, polyamide, nylon, and hytrel. A copier using the gear according to any one of claims 1 to 3 as a power transmission member. A printer using the gear according to any one of claims 1 to 3 as a power transmission member.