| 摘要 |
PURPOSE:To make it possible to apply a stable tension to belt-like plate with the use of a device for applying a tension to the belt-like plate between itself and a tension device in association with the operation of a pulley drive device, by detecting the tension of the belt-like plate and by controlling the pulley drive unit in accordance with the detection signal thereof. CONSTITUTION:Endless upper and lower belts 1, 2 are stretched between front and rear pulleys 3, 4 and 5, 6 respectively, and the belt-like plate 9 may pass through between the opposite flat sections 7, 8 of the belts 1, 2. Pressure oil chambers 11, 12 for pressing the flat sections 7, 8 against the belt-like plate 9 with the use of a pressure oil 10 are formed on the insides of the flat plates 7, 8. A motor 13 is operated to move the belt-like plate 9 in one direction between front and rear tension devices. In the above-mentioned device, there are provided a device 15 for detecting the tension of the band-like plate and a control device 16 which compares a detection signal (a) from the device 15 with a set signal (b), for delivering a control signal (c) to the motor 13. With this arrangement, the tension of the band-like plate is controlled to be always made stable. |
