Patent ID: 9399233
Filing Date: 2016-07-26
CPC Classification: B05B

Claim Text:
1. A bell cup for installation on a rotary atomizing electrostatic coating apparatus, the bell cup having a rotation axis and comprising: an inner surface; and a coating material diffusion surface on the inner surface of the bell cup, the coating material diffusion surface being supplied with a coating material, and including: a first range extending from an end part of the coating material diffusion surface to a center part of the coating material diffusion surface, the first range being a convex curved surface facing towards the rotation axis, the end part being disposed toward a proximal end of the bell cup, and a tangent line to the diffusion surface at the end part being parallel to the rotation axis, and on the convex curved surface, in a cross section of any plane that includes the rotation axis, normal line components of a centrifugal force acting on a coating material liquid film due to rotation of the bell cup are substantially equal, and a second range extending from the center part to a distal end edge of the bell cup, and being a concave curved surface facing towards the rotation axis.