The present disclosure discloses a tension device for a drive chain of a handrail system of an escalator system, a method and an escalator system including the same. The tension device for the drive chain applies pressures in opposite directions to a drive chain so as to make portions of the drive close to each other to tension the drive chain. The pressures are applied to the drive chain via a weight or a pre-loaded spring. The present disclosure also provides a method for tensioning a drive chain. The present disclosure can eliminate loosening of the drive chain after running several months, eliminate periodic heavy work on site for the escalator system and a drive system comprising the drive chain, and improve quality thereof in a simple, reliable and low cost manner.

The present disclosure discloses a tension device for a drive chain of a handrail system of an escalator system, a method and an escalator system including the same. The tension device for the drive chain applies pressures in opposite directions to a drive chain so as to make portions of the drive close to each other to tension the drive chain. The pressures are applied to the drive chain via a weight or a pre-loaded spring. The present disclosure also provides a method for tensioning a drive chain. The present disclosure can eliminate loosening of the drive chain after running several months, eliminate periodic heavy work on site for the escalator system and a drive system comprising the drive chain, and improve quality thereof in a simple, reliable and low cost manner.

The chain guide mechanism includes a slack side guide, a tension side guide, and a link member that is capable of rotating about a predetermined rotary shaft provided so as to be fixed to an attachment subject. The link member includes a slack side pivot portion attached rotatably to the slack side guide, and the slack side pivot portion is disposed on an opposite side of the chain that is guided by the slack side guide to the predetermined rotary shaft, and in a lower position than the predetermined rotary shaft. The slack side guide is biased by its own weight toward a side of the chain that is guided by the slack side guide.

Belt tensioning systems are provided for use with a belt transferring rotational force from a drive pulley to a driven pulley. One belt tensioning system includes a lever arm, an idler rotatably supported by the lever arm, a connecting link, a generally linear guide slot, and a weight coupled to the guide slot for generally linear movement along the guide slot. The lever arm has fixed and linking ends, and the fixed end is pivotably mounted on one side of the belt. The connecting link is pivotably coupled to the lever arm linking end and pivotably coupled to the weight. The belt is positioned between the fixed and linking ends, between the idler and the linking end, and between the idler and the guide slot. Downward movement of the weight causes the idler to increase tension in the belt. Chippers utilizing belt tensioning systems are also provided.