Patent GB-641970-A (GB)
Title: Elevator system
IPC: B66B1/14
Filed: 1947-08-01
Abstract: 641,970. Lifts. WAYGOOD-OTIS, Ltd. Aug. 1, 1947, No. 21119. Convention date, Sept. 11, 1946. [Class 40 (i)] A lift control system includes an electronic tube for a floor served by the lift, a circuit for causing the tube to conduct,so as to register a call for the floor and to slow down a lift approaching the floor. General.-The invention is described with reference to a system having two lifts EL1, EL2, Fig. 1, serving four floors. Each lift includes a starting button SB, Fig. 4, which closes the doors and starts the lift, a dooropening button DOB, a non-stop button NSB, Fig. 2, and its cancelling button NSRB, direction reversing buttons DRB, URB, Fig. 4, and floor-selecting buttons C1, C2, C3, CT, Fig. 2, and their cancelling buttons CC1, CC2, CC3, CCT. Closing the doors puts the lift in a condition to respond to both the floorselecting buttons and the lift-calling buttons U1 ... U3 for up-demands, and D2 ... DT for down demands situated at the various floors. Buttons U1 ... U3, D2.. DT are duplicated on the other side of the corridor as buttons U1<SP>1</SP> ... U3<SP>1</SP>, D2<SP>1</SP> ... DT<SP>1</SP>. All buttons consist of cold cathode tubes which ignite when their envelopes are touched and thus act as indicators as well as controllers. When the lift is moving up it stops at any floor at which a button U1 ... U3 has been fired as well as at floors selected by buttons C1 ... CT, while when it is moving down, it stops at any floor at which a button DT ... D2 has been fired as well as at floors selected by buttons C1 ... CT. If the lift is full, the attendant by touching and firing button NSB can prevent the lift stopping in response to demands by intending passengers ; in such a case if a " down " call at the second floor remains unanswered for a predetermined time (e.g. due to " down " lift being full) an up-moving lift is stopped and reversed at the second floor. Lift driving and controlling arrangements.- Associated with each lift is a selector machine 9, Fig. 1, which includes a crosshead 12 driven through a toothed tape 10, gearing and screw in accordance with the lift movements. The crosshead 12 carries a carriage 15 which is movable from a neutral position relative to the crosshead. At rest, the carriage is in the neutral position, and it is advanced a predetermined amount relative to the crosshead as the lift commences to move. Thereafter it moves rigidly with the crosshead which moves in accordance with the lift until upon the appropriate circuits being closed, the carriage 15 is brought to rest. The crosshead continues to move until the carriage is once again in the neutral position when the crosshead and the lift stop. This relative motion of carriage and crosshead is effected by a torque motor AM, Fig. 4, and controls the acceleration and deceleration of the lift. The carriage carries retractible pawls co-operating with stopping lugs provided for each floor. Travelling brushes BD, BHL, BU, Fig. 2, for each car are carried by a panel on the corresponding carriage 15 and co-operate with contacts SD1 ... SDT, HL1 ... HL3, SU1 ... SU3 corresponding to the four floors respectively. Each carriage 15 also carries insulating cams CX, CY, for operating hook switches HX1 ... HXT, HCl ... HCT respectively for the four floors, and each hook is of such a length that they are actuated slightly in advance of the engagement of the brushes BD, BHL, BU with the corresponding floor contacts for both up and down travel. The crosshead of each car carries a brush DB, Fig. 3, which engages stationary contacts TTC, LTC for the terminal floors. Putting a lift into service.-A lift on the first (lowest floor) out of service is put into service by (1) closing switch IS, Fig. 2, to put car buttons CT, C3, C2, C1 into circuit and to light PC1 on the first floor to indicate the presence of the lift, and (2) by starting a motor generator to energize the circuit of Fig. 4. Starting a lift.-The attendant ignites button SB, Fig. 3, to actuate relay KR to close contacts KR1, KR2, Fig. 4, preparing the circuit of field windings AMF1, AMF2 of torque motor AM and relays H, UD or DD respectively. The firing of tube SB, Fig. 3, applies a voltage sufficient to fire tube DCB which operates door-closing relay DC, the doors closing contacts DL, GS1, GS2, Fig. 4. Relay DC energizes relay PM, Fig. 4, which retracts the pawls carried by the carriage 15 and completes the circuit of motor AM to move the carriage 15 relative to 'the crosshead 12. The carriage closes contacts 1LS, 3LS, Fig. 4, to actuate relays H, EX respectively. Relay H operates relay BR to remove the brake from motor 1 M of Fig. 4), short circuits RM to energize field winding MF and removes the shunt GF from the armature GA of motor M. Relay EX opens contacts EX4 to de-energize relay PM, the pawls however remaining retracted. The closure of contacts 1LS actuates either relay UD or DD, Fig. 4, depending on whether the lift is to go up or down, to energize generator field winding GF in the appropriate direction to drive hoist motor M. Relay BR energizes relay BK which removes the short circuit from the brake cooling resistance RB and releases relay XA which in turn operates relay E to open contacts E1 rendering the door-opening relay DO, Fig. 3, ineffective. Relay E also shunts resistance RG, Fig. 4, to run the motor M at speed and actuates relay SO which locks and breaks the circuit of button SB. As the lift moves, a brush ADB on the crosshead leaves contact ALC to de-energize relay HLS to ignite tube URB in the lift as an up-moving indicator. Closing doors without starting the lift. The attendant fires tube DCB, Fig. 3, which operates relay DO but does not operate relay KR so that the torque motor AM, Fig. 4, is not started. Opening doors.-The attendant fires tube DOB, Fig. 3, to energize relay DO which opens lift doors. If SB is fired, relay E, Fig. 4, is energized to break the circuit of tube DOB so that the doors cannot be opened until tube SB is extinguished. Response to requirements of passengers in the lift.-With the lift on the lowest floor and lift buttons C2, C3, Fig. 2, ignited, tube HCR fires to actuate relay HJ. Relay HJ ignites the up-going indicator tube URB, Fig. 3, in the lift and opens the circuit of relay HR, Fig. 4, so that when the lift starts relay HR is not actuated by the actuation of relay HLS. When the carriage carried cam CY, Fig. 2, engages hook switch HC2, the circuit of tube CCP is prepared for completion by the closing of switch S1 when the lift reaches cam TC2 at the second floor. The ignition of tube CCP energizes the pawl reset relay PM of Fig. 2, to release the pawls carried on the carriage 15, and immediately de-energizes itself, the pawls remaining released. Relay PM, Fig. 2, also opens the circuit of the torque motor AM, so that the carriage is arrested although the crosshead stills moves with the lift. The crosshead thus opens contacts 3LS, 1LS, Fig. 4, to release relays E, EX, Hand UD. Relay E reinserts resistance RG in the hoist motor circuit to decelerate the lift and prepares the circuit of door-opening relay DO, Fig. 3. Relay EX opens the circuit of the pawl reset relay PM, Fig. 2, prepares the circuit of the pawl retracting relay PM, Fig. 4, for operation when the doors close, and prepares the circuit of the direction controlling relay DG, Fig. 3. Relay H, Fig. 4, releases relay BR to apply the brake, while relay UD stops the hoist motor M. As the lift arrives at the second floor, the brush CX. Fig. 2, engages hook switch HX2 to extinguish the car button C2 and light indicator PC2 on second floor. The lift restarts as described above, and when brush CY, Fig. 2, engages hook switch HC3, brush BHL is still below HL3 so that tube HCR is maintained conducting over contacts HLC; relay HJ is thus maintained until brush BHL engages contact HL3 to find no potential thereon (as there is no higher call) so that tube HCR is extinguished and relay HJ releases to operate relay HR, Fig. 4. The sequence of operations is then as for the second floor until as the lift stops and contacts H2, EX2, Fig. 3, close, direction controlling relay DG is energized over its reset 'coil. Reset coil DG prepares relay DD for actuation by the door-closing switches GS1, DL in place of relay UD, and thus reverses the energizing circuit of hoist motor M. Relay DG also extinguishes the lift up-indicator URB and ignites the down indicator DRB, reverses the connections of the torque motor and ignites lift button Cl to create a call to the lowest floor. In the absence of any other call, the lift will go down to the lowest floor on closing the doors. On reaching the lowest floor, limit switches SS2, SS4, Fig. 4. open to assure slowing and stopping, lift button C1 is extinguished and landing lamp PC1 lit, while relay H energizes the set coil of relay DG over brush DB and contact LTC to extinguish the lift down button DRB to reverse the direction circuits, and to actuate relay DGX, Fig. 4, to prepare the reset coil of relay DG for operation. Response to a demand from a floor.-The ignition of call buttons U2, U2<SP>1</SP> and indicator WPU2 by a person desiring to ascend from the second floor puts a potential on contact SU2 and tube HCR is fired to operate relay HJ and thus ignite the lift indicator URB to indicate to the attendant that a demand exists. If, further tubes D3, D3<SP>1</SP> and indicator WPD3 are ignited by a person desiring to descend from the third floor, a potential is put on contact SD3 and an alternative circuit established for tube HCR. The attendant ignites tube SB, and as the lift rises tube HCR remains lit since contact HLC alternates with HL1, HL2, HL3. Brush BD picks up a potential at SU2, to fire tube LCP and operate the pawl-releasing relay PM, Fig. 2, to initiate the stopping of the lift at the second floor. Relay PM fires tube LCC to extinguish tubes U2, U2<SP>1</SP> and WPU2 and then quenches itself, but tube HCR remains li