JP2648539B

PURPOSE:To prevent soil from depositing on V-shaped annular recessed grooves and the revolution of an endless belt from slipping in V-shaped pulleys for guiding the revolution of the endless belt. CONSTITUTION:Annular recessed grooves 33 of nearly V-shaped cross section are formed on the outer peripheral parts of the front and rear pulleys 23 and 24. Plural removing grooves 35 are formed at an interval on the peripheral lateral sides of either 23 or 24 of the pulleys. The plural removing Grooves 35 are formed and allowed to communicated with bottoms 36 of the annular recessed grooves 33. Endless protruding ridges 38 of nearly V-shaped cross section engaging with the interior of the annular recessed grooves 33 are formed on the inner peripheral parts of the endless belts 25 and 26.