| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a derailment prevention structure for a chain that prevents a chain connected to a sludge scraper plate of a sludge scraper from being derailed from a sprocket.SOLUTION: Teeth of a sprocket wheel include a protruding part which protrudes higher than another portion over a height of a link of a chain either forwards or backwards in a rotating direction of the sprocket wheel. A sludge scraper plate attached to the link forming the chain is disposed disproportionately either forwards or backwards in a direction of travel of the chain reversely to a position of the protruding part of the teeth. When the sprocket wheel is rotated, the protruding part of the teeth does not interfere with the sludge scraper plate of the link which is latched to the teeth, and the chain can be traveled.</p> |
