Planetary gear assembly, drive unit including the planetary gear assembly, and image forming apparatus including the drive unit, and installation method for planetary gear assembly

Abstract

A planetary gear mechanism includes a plurality of planetary gears, an outer gear, a sun gear, a carrier, and a stick mount. The outer gear meshes with the plurality of planetary gears. The sun gear is coaxially disposed on the same axis as the outer gear and transmits force to the planetary gears. The carrier rotatably supports the plurality of planetary gears and is rotatably and floatingly supported. The carrier includes a hole through which a stick member penetrates in a direction of axis of rotation of the carrier. The stick member penetrates through the hole and is mounted on the stick mount. The stick mount is disposed opposite the carrier. The outer gear and the sun gear are held such that one of the outer gear and the sun gear does not rotate.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This patent application is based on and claims priority pursuant to 35 U.S.C. §119 to Japanese Patent Application No. 2012-085066, filed on Apr. 3, 2012, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]Exemplary aspects of the present invention generally relate to a planetary gear assembly, a drive unit including the planetary gear assembly, and an image forming apparatus including the drive unit, and a method for assembling the planetary gear assembly.[0004]2. Description of the Related Art[0005]Related-art image forming apparatuses, such as copiers, facsimile machines, printers, or multifunction printers having at least one of copying, printing, scanning, and facsimile capabilities, typically form an image on a recording medium according to image data. Thus, for example, a charger uniformly charges a surface of an image ...

AI Technical Summary

Benefits of technology

The patent text describes an improved planetary gear mechanism and a method of assembling it. The mechanism includes a plurality of planetary gears, an outer gear, a sun gear, a carrier, and a stick mount. The outer gear meshes with the planetary gears while the sun gear is coaxially disposed on the same axis as the outer gear and transmits force to the planetary gears. The carrier rotatably supports the planetary gears and is rotatably and floatingly supported. The carrier has a hole through which a stick member penetrates in a direction of axis of rotation of the carrier. The stick member is mounted on the stick mount which is disposed opposite the carrier. The mechanism allows for easy assembly and disassembly of the gears. The technical effects of the invention include improved load bearing capacity, higher efficiency, and reduced noise.

Problems solved by technology

In such a configuration in which the carrier is floatingly supported, planetary gears may not properly mesh with the gear teeth of the outer gear or a sun gear, and tooth meshing errors occur.

By contrast, when assembled improperly, that is, when the tooth meshing errors occur, the number of the center tooth of the planetary gear meshing with the sun gear is not half the total number of gear teeth of the planetary gear when counting from the center tooth of the planetary gear meshing with the outer gear.

As a result, tooth meshing errors occur.

When the tooth meshing errors occur, the planetary gears receive uneven loads, hindering proper transmission of power, which results in various problems such as degradation of imaging quality, noise, and damage to devices.

Images