| 摘要 |
This invention relates to a chain conveyor wherein the tension of the chain or chains thereof is controlled by a closed-loop servo system. The servo-system includes an electrically-operable servo-device. An electrical signal dependent on the torque of an electric motor driving the conveyor is applied to the servo-device for operation thereof to control a piston-and-cylinder device which is adapted to alter the distance between a chain-driving sprocket and another sprocket of the conveyor. The arrangement controls the tension of the or each chain at the point where the chain is just leaving the circumference of the first-mentioned sprocket, maintaining the tension at a constant value which may be near to zero under all conditions of operation. |
