US726307A - Automatic control system for elevators. - Google Patents

Automatic control system for elevators. Download PDF

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US726307A
US726307A US13879703A US1903138797A US726307A US 726307 A US726307 A US 726307A US 13879703 A US13879703 A US 13879703A US 1903138797 A US1903138797 A US 1903138797A US 726307 A US726307 A US 726307A
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control
car
relay
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B1/00Control systems of elevators in general
    • B66B1/02Control systems without regulation, i.e. without retroactive action
    • B66B1/06Control systems without regulation, i.e. without retroactive action electric
    • B66B1/14Control systems without regulation, i.e. without retroactive action electric with devices, e.g. push-buttons, for indirect control of movements
    • B66B1/16Control systems without regulation, i.e. without retroactive action electric with devices, e.g. push-buttons, for indirect control of movements with means for storing pulses controlling the movements of a single car or cage

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  • This invention relates to electric systems of control for elevators, and particularly to the system of electric control set forth in Letters Patent of the United States granted to me February 25, 1902, and numbered 604,158.
  • Letters Patent there is described a system in which there are main or press the proper car push-button to bring him to whatever landing he desires, the relation between the operating and control circuits, the car push-buttons, and door-switches in that system being such that from the time he has opened the door at the landing of departure until he has closed the same and from the time the car starts until the car has stopped at its destination there can be no outside interference with said car.
  • One object of this invention is to provide means in connection with the foregoing system whereby there can be-no outside interference with the car after it has stopped at its destination and before its passenger has alighted from the car and closed behind him the door of the landing.
  • Another object of this invention is to provide means in the operating or push-button circuit for opening said circuit immediately upon the closing of the control-circuit.
  • Figure 1 is a view of a switchboard with certain parts of the apparatus embodying the present system of control secured thereon.
  • Fig. 2 is a diagram illustrating the several circuits of the present system and their relation to each other and to the parts shown on the switchboard.
  • the operating or push-button circuit is adapted to be opened by the movement of the resistanceregulating arm G.
  • the movement of this arm which movement is controlled by accelerating-magnet G, will be somewhat sluggish at first, the elevator being under way some few seconds before said arm starts to move, and for this reason it is preferable to provide some means for opening the push button circuit immediately upon the closing of the control-circuit.
  • Such means are furnished by providing contactsj and 3' in the push-button circuit, which contacts are arranged in operative relation with a contact- ,plate 0 on the core of the relay or lookingmagnet O. In this way the movement of the core of relay O, Which takes place immedi ately upon the closing of the control-circuit and which is substantially simultaneous with the starting of the car, will open the operating or push-button circuit at the contactsj andf.
  • the operating or push-button circuits are adapted to be closed by their respective car push-buttons 1', 2, 3, and 4 and by their respective landing-buttons 1, 2, 3, and 4.
  • Each of these circuits is arranged to pass through all of the door-switches S and one of the relays a, a a and a.
  • any one of the operating or push-button circuits will travelas follows: from the positive side of the main currentswitch W to conductor 10, through the doorswitches S, through the slack-cable stop S, through the stop-button B, through a car push-button and one of the conductors y (in case the car is directed from within; otherwise through a landing push-button and one of t e conductors 'y) to one of the relays a, a a pr a, to conductor 15, to contact j throu contact-plate 0 to contactj to the negath side of the main current-switch W, to and thjough the source of current-supply, thus completing said circuit.
  • the current through any of the operating or push-button circuits just described will energize its corresponding relay, whereby the core of said relay is actuated to close the control-circuit.
  • the control-circuit which actuates a lockingmagnet O, which magnet operates means for mechanically engaging and positively looking all of the operating-circuit relays in the inoperative position, save the one first actuated is as follows: starting from the positive side of the main switch, through the wire 10, through the door-switches S, through the wire 11, through the emergency-stop B, through the wire 12, through the wire 13, to and through the coil of the locking-magnet O to one side of the controlling-switch V, through wire 17, through the contacts B, through one of the wires :0, to one of the floor-limit switches u, through wire 31, to and through the coil of the directingmagnet D, through wire 30, through contact 29 across to contact 22 of the down circuit-breaker, through wire 37 to and through the coil of the circuit-breaker relay I, through wire 21, through contactj, to and through the resistance
  • the main or motor circuit through the reversing-switch and resistance-coil is as follows when the car is running up: from the positive side of the main switch by wire 30 to contact 32 on main upper-limit switch, to contact 34 on same switch by wire 35, to contact 36 on the up reversing-switch, to contact 37 when switch is closed, by wire 38 to contact 39, by wire 40 to terminal 41 on metor, to brushes 42 42, from brushes 43 43 to terminal 44., by wire 45 to contact 46, by wire 47 to contact 48, to contact 49 when switch is closed, by wire 50 to contact 51, by wire 52 to contact-plate 53 on resistance-regulator, by wire 54 to terminal 55 on motor, through series fieldcoils F F F F to terminal 56 on motor, by wire to one end of 57 of the resistance-coil, through the resistance-coil and contact-arm to terminal 58, by wire 59 to the negative side of main switch to and through the source of supply, thus completing the circuit.
  • the resistance-regulating arm G adapted to be actuated by an accelerating-magnet G, is provided to gradually accelerate the speed of the car after said car has been set in motion by gradually cutting out the resistance in the main circuit, a latch being provided to retain said arm after all the resistance in said circuit has been cut out and releasing said arm when the car stops.
  • auxiliary circuit Jrovided and will now be described.
  • the primary object of such auxiliary circuit is to prevent the relays in the operating-circuit from becoming unlocked as soon as the control-circuit is broken, which occurs, as before explained, when the car comes to a step.
  • auxiliary circuit is made to pass through the coil of the locking-magnet 0, whereby said magnet continues to be energized and the relays to be looked after the current in the controlcircuit has ceased to flow and until the current through said auxiliary circuit is broken.
  • Said auxiliary circuit is provided for by add- IIO ing to the system shown and described in Letters Patent No. 694,158, above referred to, a wire or conductor 0, connecting the negative side of the main current-switch V with the terminal or contact 0 and by inserting a terminal or contact 0 in conductor 20, connections being adapted to be made between said terminals by the contact-plate 0 provided upon the end of the core of thelocking-magnet 0.
  • contact-plate c When said locking-magnet is energized, contact-plate c is moved away from contactsj andj to connect contacts 0 and 0 whereby current will flow in the following circuit: from the positive side of the main current-switch W to conductor 10, through the door-switches S, through conductor 11, stop button 13, and conductor 12, to and through the coil of magnet O to terminal 0 through contact-plate c to conductor 0 to the negative side of the main current-switch, thus completing the auxiliary circuit.
  • lamps may be placed in said circuit on conductor c in order to indicate when the current is flowing through said circuit.
  • a system of electric control for elevators the combination of an operating-circuit, a control-circuit in operative relation therewith, means for furnishing power to drive a car, means for making the control-circuit independent of the operating-circuit while a car is moving, and an auxiliary circuit adapted to be closed by the last-named means, and codpcrating with said means to make the controlcircuit independent of the operating-circuit after the car has come to rest.
  • a system of electric control for elevators the combination with a car, means for supplying power to drive said car, and a stopbutton in said car, of an operating-circuit, relays arranged to be actuated by said operating-circuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the first-named relays, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, whereby said relay continues to be energized after the controlcircuit is opened and until the current in said auxiliary circuit is broken at said stopbutton.
  • a car means for supplying power to drive said car, and doorswitches at the several stations, of an operating-circuit, relays arranged to be actuated by said operating-circuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the first-named relays, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, whereby said relay continues to be energized after the control-circuit is opened and until the current in said auxiliary circuit is broken at any of said door-switches.

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  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Elevator Door Apparatuses (AREA)

Description

No. 726,307. E'ATENTED APR. 28, 19 03.
B. N. JONES.
AUTOMATIC CONTROL SYSTEM FOR ELEVATORS.
Lrrmouxox FILED JAN. 13,1903.
10 10mm. 2 SHEETS-SHEET 1.
No. 726,307. PATENTED1APR;28, 1903'. B. N. JONES.
AUTOMATIC CONTROL SYSTEM FOR ELEVATORS.
APPLICATION FILED JAN. 13, 1903. H0 MODEL. k 2 SHEETS-8HEET 2.
THE Noam: PETERS co, PHQTO-LH'HO. WASHINGTON, :m:v
UNITED STATES PATENT EEICE,
BENJAMIN N. JONES, OF EAST ORANGE, NEW JERSEY.
AUTOMATIC CONTROL SYSTEM FOR ELEVATORS.
SPECIFICATION forming part of Letters Patent No. 726,307, dated April 28, 190 7 Application filed January 13, 1903. Serial No. 138,797. (No model.) 1
To aZZ whom it may concern.-
Be it known that I, BENJAMIN N. JONES, a citizen of the United States, residing in East Orange, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Automatic Control Systems for Elevators, of which the following is a specification, reference being bad tothe accompanying drawings.-
This invention relates to electric systems of control for elevators, and particularly to the system of electric control set forth in Letters Patent of the United States granted to me February 25, 1902, and numbered 604,158. In said Letters Patent there is described a system in which there are main or press the proper car push-button to bring him to whatever landing he desires, the relation between the operating and control circuits, the car push-buttons, and door-switches in that system being such that from the time he has opened the door at the landing of departure until he has closed the same and from the time the car starts until the car has stopped at its destination there can be no outside interference with said car.
One object of this invention is to provide means in connection with the foregoing system whereby there can be-no outside interference with the car after it has stopped at its destination and before its passenger has alighted from the car and closed behind him the door of the landing.
Another object of this invention is to provide means in the operating or push-button circuit for opening said circuit immediately upon the closing of the control-circuit.
In the accompanying drawings, Figure 1 is a view of a switchboard with certain parts of the apparatus embodying the present system of control secured thereon. Fig. 2 is a diagram illustrating the several circuits of the present system and their relation to each other and to the parts shown on the switchboard.
The several parts of the system referred to herein-such as the relays, the locking de: vice. the floor-limit switches, the resistanceregulating arm, &c.are discussed in detail and completely described in the above-mentioned Letters Patent, and for this reason when these parts are referred to in the present application it will be understood that they may be of the form and charactershown and described in the said Letters P-atent. Moreover, inasmuch as the operation of the system of elevator control described in said Letters Patent is completely set forth therein it will be unnecessa y in the present application to do more than trace the several circuits of said system in so far as it may be necessary for a complete understanding of the present invention.
In the old system, as is fully described in the Letters Patent above referred to, the operating or push-button circuit is adapted to be opened by the movement of the resistanceregulating arm G. The movement of this arm, however, which movement is controlled by accelerating-magnet G, will be somewhat sluggish at first, the elevator being under way some few seconds before said arm starts to move, and for this reason it is preferable to provide some means for opening the push button circuit immediately upon the closing of the control-circuit. Such means are furnished by providing contactsj and 3' in the push-button circuit, which contacts are arranged in operative relation with a contact- ,plate 0 on the core of the relay or lookingmagnet O. In this way the movement of the core of relay O, Which takes place immedi ately upon the closing of the control-circuit and which is substantially simultaneous with the starting of the car, will open the operating or push-button circuit at the contactsj andf. v
The operating or push-button circuits are adapted to be closed by their respective car push-buttons 1', 2, 3, and 4 and by their respective landing-buttons 1, 2, 3, and 4. Each of these circuits is arranged to pass through all of the door-switches S and one of the relays a, a a and a. The current, therefore, through any one of the operating or push-button circuits will travelas follows: from the positive side of the main currentswitch W to conductor 10, through the doorswitches S, through the slack-cable stop S, through the stop-button B, through a car push-button and one of the conductors y (in case the car is directed from within; otherwise through a landing push-button and one of t e conductors 'y) to one of the relays a, a a pr a, to conductor 15, to contact j throu contact-plate 0 to contactj to the negath side of the main current-switch W, to and thjough the source of current-supply, thus completing said circuit. The current through any of the operating or push-button circuits just described will energize its corresponding relay, whereby the core of said relay is actuated to close the control-circuit. The control-circuit which actuates a lockingmagnet O, which magnet operates means for mechanically engaging and positively looking all of the operating-circuit relays in the inoperative position, save the one first actuated, is as follows: starting from the positive side of the main switch, through the wire 10, through the door-switches S, through the wire 11, through the emergency-stop B, through the wire 12, through the wire 13, to and through the coil of the locking-magnet O to one side of the controlling-switch V, through wire 17, through the contacts B, through one of the wires :0, to one of the floor-limit switches u, through wire 31, to and through the coil of the directingmagnet D, through wire 30, through contact 29 across to contact 22 of the down circuit-breaker, through wire 37 to and through the coil of the circuit-breaker relay I, through wire 21, through contactj, to and through the resistance-regulating-arm wire 16 to the negative side of the main switch, to and through the source of supply to the positive side of said switch, thus completing the circuit. As a result of this the locking-magnet will be energized, thus locking the core on relay 4 up in the operative position and the cores of all the other relays in the inoperative position. Directing-magnet D will be energized and its core being raised will close the main circuit.
The main or motor circuit through the reversing-switch and resistance-coil is as follows when the car is running up: from the positive side of the main switch by wire 30 to contact 32 on main upper-limit switch, to contact 34 on same switch by wire 35, to contact 36 on the up reversing-switch, to contact 37 when switch is closed, by wire 38 to contact 39, by wire 40 to terminal 41 on metor, to brushes 42 42, from brushes 43 43 to terminal 44., by wire 45 to contact 46, by wire 47 to contact 48, to contact 49 when switch is closed, by wire 50 to contact 51, by wire 52 to contact-plate 53 on resistance-regulator, by wire 54 to terminal 55 on motor, through series fieldcoils F F F F to terminal 56 on motor, by wire to one end of 57 of the resistance-coil, through the resistance-coil and contact-arm to terminal 58, by wire 59 to the negative side of main switch to and through the source of supply, thus completing the circuit.
The resistance-regulating arm G, adapted to be actuated by an accelerating-magnet G, is provided to gradually accelerate the speed of the car after said car has been set in motion by gradually cutting out the resistance in the main circuit, a latch being provided to retain said arm after all the resistance in said circuit has been cut out and releasing said arm when the car stops. Upon the movement of said resistance-regulating arm the control-circuit is broken at contact jj,
but the current continues to flowin said circuit, because the core of the circuit-breaker relay I is raised and connection is made between the contacts m and m, the controlcircuit as established thereby being traced as follows: from the negative side of the main switch through the main wire 16, the pivot-pin on the resistance-regulating arm, the conductor 00 the contact 00, through contacts m and m',thence through circuit-breaker coil I, thence to conductor 37, the remaining part of the control-circuit being the same as previously described.
It will be obvious that the breaking of the push-button or operating circuit at contacts j and j will prevent any outside interference with the car after it is once in motion, even though the locking device should fail to work. When the car has reached its destined landing, the floor-limits will operate to break the control-circuit, which in turn operates to break the motor or main circuit, stop the car, and restore the system to its normalor initial condition. It will be noted, however, that inasmuch as the normal or initial condition of the system. is established as soon as the car is brought to a stop the car might in the old system be at once set in motion by pressing any of the floor push-buttons, even before the occupant of the car has had time to open the landing-door, which breaks all the operating-circuits through door-switches S. In order to prevent such outside interference with the car after the car has come to a stop and before the occupant thereof opens the door of the landing where he is to alight, an auxiliary circuit is Jrovided and will now be described. The primary object of such auxiliary circuit is to prevent the relays in the operating-circuit from becoming unlocked as soon as the control-circuit is broken, which occurs, as before explained, when the car comes to a step. For this purpose the auxiliary circuit is made to pass through the coil of the locking-magnet 0, whereby said magnet continues to be energized and the relays to be looked after the current in the controlcircuit has ceased to flow and until the current through said auxiliary circuit is broken. Said auxiliary circuit is provided for by add- IIO ing to the system shown and described in Letters Patent No. 694,158, above referred to, a wire or conductor 0, connecting the negative side of the main current-switch V with the terminal or contact 0 and by inserting a terminal or contact 0 in conductor 20, connections being adapted to be made between said terminals by the contact-plate 0 provided upon the end of the core of thelocking-magnet 0. When said locking-magnet is energized, contact-plate c is moved away from contactsj andj to connect contacts 0 and 0 whereby current will flow in the following circuit: from the positive side of the main current-switch W to conductor 10, through the door-switches S, through conductor 11, stop button 13, and conductor 12, to and through the coil of magnet O to terminal 0 through contact-plate c to conductor 0 to the negative side of the main current-switch, thus completing the auxiliary circuit. If desired, lamps may be placed in said circuit on conductor c in order to indicate when the current is flowing through said circuit.
In the operation of the present system when the elevator comes to a stop current will continue to flow, notwithstanding the break in the control-circuit, through locking-magnet O, which is included in the auxiliary circuit, and said circuit can only be broken through stop-button B or through the door-switches S. Accordingly the occupant of the car still has the elevator under control after said elevator has come to a stop and may do one of two things-either open the door of the landing at which the car has stopped, thus break ing the auxiliary circuit and unlocking the relays in the operating-circuit, or break the auxiliary circuit through stop-button B. In the first case one of the switches S will be opened, and accordingly until the landingdoor is again closed the car cannot be operated from any of the push-buttons, while in the second case the occupant still remains in the car and having restored the system to its normal or initial condition through button B he may press any of the car push-buttons and send the car to another landing.
While the present invention has been described in connection with the system of electric control set forth in Letters Patent No. 604,158, it will be understood that said invention is not to be construed as limited. in its application to that system alone.
I claim as my invention- 1. In a system of electric control for elevators, the combination of an operating-circuit, a control-circuit in operative relation therewith, means for furnishing power to drive a car, means for making the control-circuit independent of the operating-circuit while a car is moving, and an auxiliary circuit adapted to be closed by the last-named means, and codpcrating with said means to make the controlcircuit independent of the operating-circuit after the car has come to rest.
2. In a system of electric control for elevators, the combination of an operating-circuit, a control-circuit in operative relation therewith, means controlled by said control-circuit for furnishing power to drive a car, means also controlled by said control -circuit for making that circuit independent of-the operating-circuit while the car is moving, and an auxiliary circuit adapted to be closed by said last-named means and cooperating with said means to make the control-circuit independent of the operating-circuit after the car has come to rest.
3. In a system of electric control for eleva-- tors, the combinationof an operating-circuit, relays arranged to be actuated by said operating-circuit, a controlcircuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the first-named relays, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, whereby said relay continues to be energized after the controlcircuit is opened and until the current in said auxiliary circuit is broken.
4:. In a system of electric control for elevators, the combination with a car, means for supplying power to drive said car, and a stopbutton in said car, of an operating-circuit, relays arranged to be actuated by said operating-circuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the first-named relays, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, whereby said relay continues to be energized after the controlcircuit is opened and until the current in said auxiliary circuit is broken at said stopbutton.
5. In a system of electric control for elevators, the combination of a car, means for supplying power to drive said car, and doorswitches at the several stations, of an operating-circuit, relays arranged to be actuated by said operating-circuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the first-named relays, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, whereby said relay continues to be energized after the control-circuit is opened and until the current in said auxiliary circuit is broken at any of said door-switches.
6. In a system or" electric control for elevators, the combination of an operating-circuit, relays arranged to be actuated by said operating-circuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted while energized to lock the firstnamed relays, floor-limits in said control-circuit by which said circuit is adapted to be opened, and an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay whereby said second relay continues to be energized after the control-circuit is opened by any of said floor-limits and until the current in said auxiliary circuit is broken.
7. In a system of electric control for elevators, the combination with a car, means for supplying power to drive said car, a stop-button in said car, and door-switches at the several stations, of an operating-circuit, relays arranged to be actuated by said operatingcircuit, a control-circuit adapted to be closed by any of said relays, a second relay arranged to be actuated by said control-circuit and adapted While energized to lock the firstnamed relays, floor-limits in said control-circuit by which said circuit is adapted to be opened, an auxiliary circuit adapted to be closed by said second relay, said auxiliary circuit being arranged to pass through said second relay, stop-button and door-switches whereby said second relay continues to be energized after the control-circuit is opened by any of said floor-limits, and until the current in said auxiliary circuit is broken at said stopbutton or at any of the door-switches.
8. In an electric-control system for elevators, the combination of operating and control circuits, a relay to close the control-circuit for each floor, a push-button for operating said relay, means for positively engaging and mechanically locking, in the inoperative position, all relays, save the one first actuated, and an auxiliary circuit adapted to be closed by said means and cooperating with the same for the purpose specified.
9. In a control system for electric elevators, the combination of a control-circuit, an operating-circuit for closing the control-circuit, an auxiliary circuit, and a single relay in both said control and auxiliary circuits adapted when energized to open the operating-circuit and to close said auxiliary circuit for the purpose specified.
10. In a control system for electric elevators, the combination of a control-circuit, an
operating-circuit for closing the control-circuit, an auxiliary circuit, and a single relay in both said control and auxiliary circuits, a contact-plate on the core of said relay, said contact-plate being normally in the operating-circuit and adapted when said relay is energized to open said operating-circuit and to close said auxiliary circuit for the purpose specified.
This specification signed and witnessed this 7th day of December, 1902.
BENJAMIN N. JONES. In presence of O. ALF. SANDBORGH, JOHN B. M. SHOWELL.
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