black foam belt.
The timing belt body is composed of a strong layer, a toothed layer, a covering layer and a rubber layer. The strength layer is a core rope with high tensile strength, which is usually surface-treated glass fiber, polyaramid fiber or steel wire rope. This layer mainly bears the tensile force of the load.
The toothed layer is the part where the timing belt is in contact with the pulley, and the root line of the toothed layer is generally at the position of the pitch line to ensure that there is no change in the pitch during bending. The tooth profile must be accurate and not easily deformed to accurately transfer motion.
The covering layer is wrapped on the entire toothed layer to protect and prevent cracking. The adhesive layer is also called the belt back, and its main function is to adhere the tensile material of the strong layer to the knot line position of the belt and protect the tensile material.