FIELD: railway transport. SUBSTANCE: invention relates to materials handling equipment. Proposed device has crane 3 with boom 4 and clamshell 5. Point- type light emitter 6, light receiver 7 and actuating unit 8 are installed in crane cabin. Light reflector 9 is mounted on boom. Light receiver is made in form of strip assembled on point-type photodetectors. Output of light receiver is connected with input of actuating unit signaling that clamshell has been lowered to preset pint or stopping the boom automatically. EFFECT: increased capacity, improved safety of open-top cars. 1 dwg
