Patent ID: 8317014

Claim:
A belt conveyor comprising: an endless loop belt which is wrapped around pulleys at both ends thereof and is configured to revolve; and a first belt reversing mechanism and a second belt reversing mechanism which are provided at an upstream portion and a downstream portion of a return belt, respectively, in a belt movement direction, and are configured to reverse the belt 180 degrees; wherein each of the first and second belt reversing mechanisms includes two sets of pinch rollers which are provided so as to be spaced apart from each other in a belt movement direction and configured to support the belt, and one or more sets of guide roller mechanisms which are provided so as to be spaced apart from each other in the belt movement direction and are configured to guide the belt in a tubular shape from outside between the pinch rollers such that the belt is reversed 180 degrees and twisted to cause a center portion of a span between the pinch rollers to form a tubular open cross-section with a dirty surface facing inward; and wherein the belt between the two sets of pinch rollers forms a catenary curve or a curve close to the catenary curve, the catenary curve being defined by a weight of the belt per unit length, a tension applied to the belt, and the span between the pinch rollers, and the guide roller mechanisms are provided at the belt forming the catenary curve or the curve close to the catenary curve.