Patent GB-1488206-A (GB)
Title: Elevator control apparatus
IPC: B66B1/52
Filed: 1975-08-05
Abstract: 1488206 Controlling elevators HITACHI Ltd 5 Aug 1975 [9 Aug 1974] 32722/75 Heading B8L An elevator control apparatus for generating a command for decelerating and stopping the elevator car at a floor generating a call, comprises a synchronizer 9 movable in proportion to the movement of the elevator car 1, an advancer 13 driven by a separate device in advance of the synchronizer, stop means to arrest the advancer upon detection thereof at a calling floor level, and a movable detector 22 for detecting the distance between the synchronizer and advancer, the detector 22 being driven in proportion to the difference in movement between the synchronizer and advancer, and having means 23, 24 for detecting its position. The synchronizer 9 is movable along a vertical guide 26 by a chain 7 passing around pulleys 5, 5<SP>1</SP> driven through reduction gearing from the elevator operating drum 3. The advancer 13 is movable along a vertical guide 25 by an endless chain 8 to which it is secured, the chain 8 passing around idler pulleys 14, 15, 16, 17, 6<SP>1</SP> and a pulley 6 driven from the operating drum 3, at the same speed as pulley 5, the two pulleys 5 and 6 being the same diameter. The difference detector 22 movable along a vertical guide 27 has pulleys 20, 21 thereon over which two bights of the chain 8 are looped. The detector arrangement 23, 24 detects movement of the difference detector 22 from a vertical position representing zero difference in position between the synchronizer 9 and advancer 13. Each elevator floor is represented by detectors 191, 192 ... 19n and 121, 122 ... 12n associated with detectable objects 18 and 11 on the advancer and synchronizer. A first part 81 of the chain 8 moves at the same speed as the synchronizer 9 whereas a second part 82 of the chain moves at the same speed as the advancer 13, the difference detector 22 moving in proportion to the difference in movement between the synchronizer 9 and the advancer 13. Upon command for up travel of the car 1, the separate drive for the advancer, comprising a motor driven sprocket 10 mounted on the synchronizer and drivingly engageable with part 82 of the chain 8, is energized to move the chain part 82 and advancer 13 upwardly in advance of the synchronizer which moves up in proportion to the elevating car 1. Due to the relative motion between the two chain parts 81 and 82, the difference detector 22 moves downwardly to a lower end position where the detector 23, 24 causes locking of the sprocket 10, the difference detector remaining in this position representing the maximum decelerating distance for the car. When the call floor is detected by the advancer 13, it is mechanically stopped while the synchronizer 9 continues to move upwardly and causes the difference detector to move upwardly again into its neutral position, an elevator speed command for deceleration being issued in response to an output signal corresponding to the change in position of the points of the detector arrangement 23, 24. In another embodiment the advancer motor drives the chain pulley 14. In a final embodiment of Fig. 2 (not shown) the pulley and chain system is arranged such that a greater movement of the difference detector is provided in a direction the same as that of the synchronizer and advancer.