| 摘要 |
PCT No. PCT/GB86/00321 Sec. 371 Date Jan. 28, 1987 Sec. 102(e) Date Jan. 28, 1987 PCT Filed Jun. 6, 1986 PCT Pub. No. WO86/07409 PCT Pub. Date Dec. 18, 1986.A mining machine and control system therefor for use in a possibly explosive environment, wherein the control system includes electronics within a flameproof enclosure communicating with controls outside the enclosure by way of a fiber optic link and an interface. The fibre optic link has a plurality of channels each comprising an infrared source, and outward fiber optic path, a return fiber optic path, and a detector. Between the outward and return paths, a control station is arranged to modify the light, suitably by reducing its intensity to indicate and "off" state. An alarm signal is generated in the event of no return light being detected. |
