GB862514A - Automatic control means for electrically driven mine hoisting machinery - Google Patents

Abstract

862,514. Controllers. SOC. DES FORGES ET ATELIERS DU CREUSOT. Oct. 9, 1958 [Oct. 18, 1957], No. 32235/58. Class 38 (3). [Also in Group XXX] A controller 44 for an electric motor driving a mine hoist is adjusted to provide acceleration and deceleration of the motor by means of a shaft 43 driven by a main shaft 1 which is subject to the movement of the hoist cages and is geared to spur wheels 14, 21, mounted on threaded portions 15, 22 of a fixed shaft 16. Hollow shafts 23, 24 are provided with abutments 27, 28 adapted to co-operate with dogs 29, 30 mounted on the spur wheels. When the hoist is moved away from a " top landing " position, the dog 29 engages the abutment 27 so that rotation of the hollow shaft 23 is transmitted to the sun-wheel 38 of a differential gear, the sun-wheel 37, integral with shaft 34, being locked by a stop 55 on a cam 46. The rotation of the satellite carrier 40 is transmitted to the shaft 43 until a spring-biased roller 50 on cam 45 enters a recess and turns the cam into a locking position. This represents the end of the acceleration period, and the controller occupies the normal-running position until the dog 30 engages the abutment 28 on the hollow shaft 24. The sun-wheel 38 is then locked by the stop 55 on cam 45, and the sun-wheel 37 is driven by the shaft 34 to turn the satellite carrier 40 in the opposite direction, and, with it, the shaft 43 thereby causing deceleration of the hoist. At a suitable moment the brakes are applied through the agency of limit switches. During a subsequent winding operation the hoist motor turns in the opposite direction, the dog 30 controlling the acceleration sequence, whilst the dog 29 subsequently adjusts the controller during the deceleration period. When the hoist is adapted for multiple-level service, the control of the motor at the intermediate stopping positions of the cages is effected by a further differential gear which has sun-wheels coupled respectively with the shafts 1 and 24. The satellite carrier is locked during the acceleration and deceleration periods by a brake controlled by a level selector, so that the shaft 24 is driven in the appropriate direction. The control of the motor upon approaching the extreme landings is effected by the dogs 29, 30, independently of the level selector and the further differential gear, Fig. 5 (not shown).