Patent GB-697202-A (GB)
Title: Elevator system
IPC: B66B1/18
Filed: 1951-08-28
Abstract: 697,202. Electric lift systems. OTIS ELEVATOR CO. Aug. 28, 1951 [Sept. 16, 1950], No. 20243/51. Class 40 (i). In a multi-car lift system means responsive to the continuous registration of a landing call or overlapping calls for a predetermined time automatically brings a home station car to the assistance of the busy car or cars. This so-called " continuous-call-registration control" may be combined with the usual " call-behind " and "automatic load-non-stop controls." General. The invention is shown in Figs. 2a, 2b, 3a for a two-car system serving a basement and five floors. Figs. 2a, 3a show the control and power circuits for car A. Fig. 2b shows the control circuits for car B, the power circuits therefor being similar to those shown in Fig. 3a for car A. Each car includes floor buttons CBB, CB1 .. CBT, for the basement, floor 1, floor 2 .. &c., and a switch MCC actuated when the car is loaded to a predetermined amount. The up and down landing buttons for the corresponding floors, UBB-UB1 .. UB4, DB1-DB2 .. DBT, are common to the cars. Floor selector. The selector for each lift consists of a crosshead, Fig. 1 (not shown), driven in correspondence with the car movements through a tape and chain. The crosshead carries series of brushes, UCS-CAR-DSC, UHS-UHR, DHRDHS, Figs. 2a, 2b, for engaging respective series of contacts CPB-CP1 .. CPT, UPB-UPI .. UPT, and DPB-DP1 .. DPT, for the various floors. The crosshead also drives an "up-down" direction cam FDC having a lower conductive portion and an upper insulating portion, which coacts with direction switches FHB-FB1 , . FHT, for the various floors. Separate brushes are provided in respect of up-landing calls (UHS), down-landing calls (DHS), car-up calls (UCS), car-down calls (DCS). Auxiliary up-landing (UHR), down-landing (DHR), and car-call (CAR). brushes are also provided. The crosshead carries a further brush UCB coacting with floor contacts UCC, one for each floor, for " behind-car " calls. In addition, each selector has stationary home-landing and basement contacts HLC, BLC for contacting the home landing selector brush HLB. An up-stop switch USS and a down-stop switch DSS, carried by the crosshead, are operated by cams at each floor as the car arrives thereat in the direction for which the stop switches cater. Single car operation. Assuming car A is idle, i.e., with doors closed, at the home (first) floor, and stop switches ES1b, ES2b for car B are open, a transfer switch TGa and a starting relay FCa are operated. Actuation of any landing up-button UP2a .. UPTa, for a higher floor energizes the corresponding floor relay BU, 1U .. 4U, which latches in its operated position and energizes the series connected relays LUa, AUa. AUa operates the stopping relay Sa, Fig. 3a, which in turn operates the auxiliary stopping relay SXa, and series connected switches Aa, Pa. Switch Aa connects the phases MO1a-M02a of the hoist motor MORa for up travel and PA completes the stator circuit. Both switches at the same time operate the brake release coil BRa to start the car, and operate an auxiliary door relay DLa and a switch Ka. The relay DLa operates the door relay DR and a timing relay Za. Switch Ka, which is delayed, e.g., by a dashpot, accelerates the hoist motor. As the car nears the floor corresponding to the registered landing-call the selector up brush UHSa engages the corresponding floor contact UP1a .. UPTa to energize the reset coil of the stopping relay Sa, Fig. 2a, in series with the reset coil of the actuated floor relay 1U .. 4U. The stopping relay resets, de-energizes SXa, and increases the current flow to reset the operative floor relay and so cancel the call. At the same time the insulating up section of the selector cain FDCa engages the corresponding direction switch FH1a .. FHTa to de-energize relays AUa, LUa, which drop out. The switches Pa, Aa, however, remain energized until the cam operated up-stop switch USSa is opened, when the hoist motor is de-energized and braked to rest. Pa, La as they relapse cause Ka, DLa to drop out; DLa energizes the door reopen relay DZa and the door open switch DOa. DOa starts the door operating motor DMRa to open the car and landing doors, while DZa maintains the time relay Za operated. As the doors start to open, a limit switch DCL2a closes to energize the auxiliary door closing relay GA. As the doors are fully opened limit switches DOL1a, DOL2a open, causing DOa, DRa to relapse to stop the door operating motor and de-energize DZa, which. breaks the circuit of the timing relay Za. The release of timing relay Za is delayed by the condenser CO4a to give passengers time to enter the car and operate a car button. Upon operation of a car button CB1 .. CBT for a higher floor, the associated floor relay BCa, 1CA .. TCa operates, latches in operated position, and by way of the appropriate direction switches FH1a . . FHTa again energize LUa, AUa. The car button relay CCa is also operated by the operative car button and operates the door close switch DCa, which in turn operates a reverse resistance relay CTa to lock DCa. DCa operates the motor DMR to close the car and landing doors when it is de-energized by a limit switch. The car button relay CCa also operates the stopping relay so that as the doors close the relays Pa, Aa are energized over the car door contacts GSa, DSa and operate as before to start the hoist motor. In this case, however, the car is stopped at the selected floor by the car up-call brush UCSa engaging the associated floor contact CPBa, CPla .. CPTa to energize the reset coil SA of the stopping relay, the car being stopped and the doors opened as before. If no further calls are registered the doors close as the timing relay Za falls. For down-car travel relays BDa, LDa and switch Ba are operated instead of AUa, LUa, Aa and brush DHSa functions for a landing call and brush DCSa for a car call to stop the car at the selected floor. The car will respond to a downlanding call during up-car travel provided it is not required to travel beyond the landing in question bv circuits already set up and vice versa. A plurality of up-landing and/or car calls are responded to in the natural order of the floors regardless of the order in which they are set up and similarly for down-landing calls. Duplex-car operation. Closing the stop switches ES1b. ES2b brings car B into operation, and it is controlled similarly to car A. A car remains idle at a floor at which it stops if no further calls are registered. Any landing call, up or down, subsequently registered is responded to by the idle car, which continues to answer landing calls until a "call behind " is received, when the other car, which normally remains at the home station, helps out the busy car. For example, if car A is called from the home floor in the up direction, the up-call-below switch UCa is maintained energized between floors over contacts UC1a, and switch UCBa, and at the floors over the associated floor contact UCCBa, UCC1a .. UCCTa. If an up-landing button UBB is now pressed for a floor behind the up moving car A, the relay UCa is de-energized as car A reaches the next floor, whereupon the starting relay FCb operates to cause car B, assumed to be at the home station, to answer the "call-behind." Similarly, if car A is moving downwards and a " call-behind," i.e.. an up-call is made, a pass coil switch PCa is operated to operate the starting relay FCb for car B to answer the call. The home station car always starts in response to a car call regardless of whether or not it is behind the other car in operation, and once it is started it becomes a busy car and stops in response to calls as mentioned above. With both cars in operation, the car which stops at a floor for which a landing call is registered is the car travelling in the proper direction whose call pick-up brush UHS, DHS first engages the appropriate floor contact, or in the case of a call for the direction opposite to car travel, the car whose upper section of cam FDC first engages its direction switch FH for that floor. When both cars are busy and one car reaches its highest call, then, provided that a " call-behind" the other car is not registered, the relays LD, BD are energized to drive the one car to the home station. In such a case, the other car, when it has answered its last call, remains at the floor at which it has stopped in response to the last call. A homing car will respond to a car-call or an intervening down-landing call before resuming its homeward journey, but should a landing call be registered behind the busy car the homing car goes to the assistance of the busy car. The home station car responds to landing calls at the basement. The other car, if free, does not home immediately but only if the car answering the basement call has to proceed to a floor above the home station. Timing control. As soon as a landing call is registered a landing relay HC, Fig. 2a, is de-energized and breaks the circuit of a timing relay TT which is, however, delayed in its release. If continuous registration of landing calls persists for the fall-off time of relay TT then a circuit is made to start the home or homing car to assist the busy car. Automatic load non-stop operation. Should the weight of passengers in a busy car be sufficient to actuate the car load switch MCCa, MCCb, the associated by-pass switch BPa, BPb is actuated, as the doors close, to prevent response of the car to intervening landing calls until the load has been reduced. The by-pass switch also causes the home or homing car to come to the assistance of the. overloaded busy car. Modifications. Cut-out switches CU1 .. CU6 are provided for each car so that by closing various combinations thereof different operating conditions may be catered for. For example, " continuouscall-registration " control, " call-behind" control, or automatic-load non-stop operation may be used singly or in various combinati