Patent ID: 8594537
Filing Date: 2013-11-26
Classification: G03G

Abstract:
1. A powder carrier screw, comprising: a rotation shaft extending in an axial direction through a path which carries powder such as toner, the rotation shaft being rotatably supported by a container forming the path, the rotation shaft having one end from which a rotation driving force is applied; a coil which is provided in a spiral form along an outer circumference of the rotation shaft, the coil including a general portion consisting of a material of a certain thickness wrapped around the rotation shaft, the coil having a shaft center of the rotation shaft as a coil shaft center and having both end portions of the coil joined to both end portions of the rotation shaft, and the coil rotating along the rotation of the rotation shaft; a thick portion which is provided in at least one end portion of the coil in the axial direction, the thick portion having a thickness larger than said certain thickness of the general portion of the coil; and a coil welded portion in which the thick portion and the rotation shaft are welded, wherein the rotation shaft has a flange on at least a portion of the outer circumference of the rotation shaft, the thick portion is located in a position capable of transferring heat to the flange in the welding of the thick portion to the rotation shaft, the flange includes a first flange portion arranged at a first position along the axial direction and a second flange portion arranged at another position along the axial direction which is relatively further, as compared to the first position, in the axial direction from the thick portion, an outer diameter of the first flange portion is different than an outer diameter of the second flange portion, and the outer diameter of the first flange portion is larger than an outer diameter of the rotation shaft to which the thick portion is welded.