US1661022A - Alternating-electric-current control system - Google Patents

Description

Feb. 28, 1928.

E. B. THURSTON ALTERNATING ELECTRIC CURRENT CONTROL SYSTEM Filed Sept. 28, 1923 safet Y ill Ill)

Patented Feb. 28, 1928.

UNITEn STATES PATENT OFFICE.

ERNEST B. THURSTON, OF TOLEDO, OHIO, ASSIGNOR TO THE HAUGHTON ELEVATOR & MACHINE C0,, 01? TOLEDO, OHIO, A CORE'ORATION OF OHIO.

ALTERNATING-ELECTRIC-CURRENT CONTROL SYSTEM.

Application filed September 28, 1923.

This invention relates to safety features in electrically controlled installations.

This invention has utility in. connection with torque motor control for polyphase electrical circuits in the operation of elevators. In its present embodiment the invention comprises an installation including a reversible polyphase alternating current motor, a power supply therefor, ma1n and direction switches, electric actuating means for the main switches, additional electric actuating means for the direction switches, a controller for the actuating means, resistance between the controller and the supply, a speed controlled governor for holding the direction switch in, when mot-or is oper ating above a predetermined speed, a connection to the controller through said direction switch and speed controlled device by-passnup said resistance and (to-acting, upon shifting the controller motor versal, to connect the main switch actuating means for a power connection which insures opening the main switch.

One object of the invention is to provide mlvphase actuating devices for the switches of? an elevator system, which enable the switches, under certain conditions, to be positively operated in either direction. An-

other object is to prevent reversal oi? the elevator motor when its speed exceeds a predetermined value.

Referring to the drawings vFig. 1 is a wiring diagram oi? an embodimeut ol? the invention in a three phase reversible two speed induction motor elevator installation, parts being broken away, and

Fig. 2 is a wiring d'hgram illustrative of the principle for efi'ecting power throwing out (it the high speed main switch on motor reversal.

In elevator shaft 1 having landings 2 is shown elevctor ear 3 having hoisting cable 4; extending around drum 5 on shaft 6 above the elevator well 1. This cable l utter passing around the drum 5e31tends about idler 7 to counterweight 8. Induction motor 9 on shaft 10 has ball governor 11, brake drum 12, and won 13 thereon. This worm 13 is in l'uesh with worm wheel ll for operating the shaft (3 and through the drum 5 and cable eliecting raising and lowering of the elevator ear 8 in the well or shaft 1 between dill'erenli landings 2. 1n the elevator car 8 1S controller 15 having contacts 16, 17.

Serial No. 665,297.

Power supply line 18 has branch 19 through resistance 20 thence by line 21 through terminals at upper stop limit switch 22 to line 23 extending to terminal 24 at the contact 16 or the controller 15. Assuming the controller 15 is shifted to the right for effecting up direction travel of the elevator car 3 in the well 1, this contact 16 is shifted to con nect the terminal 24 with terminal 25 having connection by way of line 26 through tern'iinals at door switches 27, closed when the landing doors to the elevator well 1 are closed, thence by line 28 through the coil at relay 29, and by line 30 to power supply line 31. As the initial movement of the controller 15 thus energizes the relay 29, the line 87, which is adapted to be connected to power supply line 18, when the direction switch 38 is closed, is connected through branch 36, brake coil 35, line 34, relay 29 and line 33 to power supply line 31; branch 36 is also connected through brake coil 39, line 40, relay 29 and line 41 to line 42 which, when the direction switch is closed, is connected to power supply line 43.

T 1e power supply line 43 has a branch line ll which, when the relay 29 is closed, is connected through linel5 and through resistance 46 to line 47 extending to terminal 4-8, at the contact 17 of the controller 15. At the first position of the controller 15 connecting terminals 24; and 25, this terminal 48 is not necessarily connected through contact 17 However, upon further shifting of the controller, the contact 17 is brought to the terminal 49 and thereby the terminal l8 through this contact 17 is connected with line 50 extending to winding 51 of torque motor 52. As the contact 17 engages the terminal 4-9 the contact 16 engages terminal 58 connecting the line 23 with line 54: we tending to winding 55 at the torque motor 52. Third winding 56 at this torque motor 52 has line 57 therefrom through various safety devices, as emergency switch, over travel switches, slack cable switches, safety speed governor, etc., thence by line 58 to the power supplyline 31. This torque motor or polyphase switch actuating device 52 is accordingly energized to rock shaft '59, and through up direction cam 60, to close the switch 88 and thereby connect the power supply 18 with the line 37 and the power supply line 1 3 with the line 42, ell'ective through the contacts at the relay 29 for energising the brake coils 35, 39, and thereby swinging brake shoes 61 clear of the drum 12 against the resistance oil spring 62.

The low speed switch 63 is held normally closed by a cam 80 on a rock shaft 7 9. This roclr shalt is adapted to be rocked by a torque motor 7 1 to a position for releasing the switch 63 and permitting it to open, at the same time closing the high speed main switch 32 by means 01 the cam 81. lin the normal operation of the system, as soon as the torque motor '24 is de-energized, the rock shaft 79 returns to its normal position in which the low speed switch 63 is closed. 1t is to be understood that when the shaft 79 is at the limit 01 its movement in one direction the cam 80 is effective and when it is at the other limit of its position the cam 31 is etl'ective.

Normally closed low speed switch 63 conneots the power line 31 through line 641 to low speed winding 65 at the motor 9. The

closing of the up direction switch 38 connects the power supply line 18 with the line 3"? extending to low speed winding 06. This up direction switch is also effective in connectin the power supply line 13 with the line 12, which, at the low speed switch 63 is connected to line 67 extending to low speed winding 63. Accordingly at this position of the controller 15, the motor 9 is energised for low speed operation and the bralre shoes 61 are released from the shalt so that the elevator 3 may be operated upward at low speed. Further shifting of the controller to the right, brings the contact 16 to terminal 69 connected by line Z 0 through terminals at upper slow down limit switch "6' 1, thence by line 72 to winding 13 at torque motor 7 1. As this contact 10 is moved to the terminal 69, the controller contact 1'? is brought to terminal T 1 connecting the line 4'? to line 75 extending to winding 16 at the torque motor 'Z l. 'llhird winding W at the torque motor 'M is connected by line 73 to the line 3 1 extending through terminals at the relay 29 to the line 33 connected to the power line 31. Accord ingly this main switch polyphase alternating current actuating device or torque motor W1 is ettective for rocking its shaft 7 9 to shitt slow speed switch cam 80 to permit the slow speed switch 63 to open, while high speed cam 31 on the shaft 79 throws high speed switch 32 into closed position. This closing of the high speed switch 32 connects the power supply 31 to line 83 extending to high speed winding 84: at the reversible two speed. motor 9. The power line 12 from the up direction switch 33 extends to this switch 32, is there connected to line extending 10 high speed winding 86 at the motor 9.. 'llhird high speed winding 87 for this motor 9 is connected by line 38 to the line 3'1 i llhis reversible two speed induction ind neenoae tor 9 is accordingly now connected up for high speed driving of the elevator 3 upward.

As this motor 9 gets the shaft 10 up to speed, fly ball governor 11 as a speed control device causes contact 89 to connect branch 93 from the line 36 with line 91. extending to the line This fly ball governor 11 also carries contact 92 ellective to connect branch 90 oi the line 4-1 with a line 91 leading to the line 50. This means that with thc'shai t 10 up to speed, or beyond a determined speed, this control governor 11 will bypass the controller and hold the direction switch in, even though the relay 29 be open. This not an interlock at the direction switch nor at a main switch. This mlding in is ellective with the controller 15 shi'lited baclr to central or oil position. However, even in the event of rocking the controller 15 to a reverse position, the governor 11 will still control the direction switch, for the contact 19 is engaged with contact 95 from line 90 through terminals at down stoplimit switch 9?, thence by line 93 connected to the line its this contact 10 is shifted by throwing the controller 1.5 to the left for down direction travel, the contact 10 engages terminal connected by line 100 with the line 20. This tends to hold the relay 29 closed. l urthcr shifting of the controller 15 to the left brings this contact 10 to terminal 101 connected by line 102 with the line the same time the contact 17 engaging terminal 103 from the line H is shifted over to terminal 104 connected by line 105 to the line 5 4-. This does not effect reversal of the direction switch torque motor 52, tor the reason that the governor 11 is bypassing the resistances 20, 16, and the resistances 20, 16, are in parallel with this direction switch torque motor The further throwing of this controller 15 for down direction travel, while the car 3 is still travelling upward, brings the contact 16 to terminal 106 connected by lin 107 through terminals at slow down limit switch 103, thence by line 109 to the line 72. Simultaneously the contact 1'? is shifted to terminal 110 connected by line 111 to the line 75. These connections to the windings 73, 76 oil the torque motor i l bypass the resistancos 20, In this connection, the supply line 18 is connected by way of the switch 38, lines 3'2, 30, itch 89, lines 91, 5 1, 105, terminal 10 1, contact 1'7, lines 111, 75, to the winding 70, which winding 76, had been tllGlGlO'fOIQ supplied through the contact 7 from terminal 4:8, line 47, resistance 16, line 4:5, switch 29, line li, from the supply line 13. The supply line 13 is now connected by way of the switch 38, lines 11, 90, 93, switch 92, lines 50, 102, terminal 101, contact 16, terminal 106, line 107, switch 108, lines 109, 72, to the winding 73, which winding 73 had been tncretolore supplied tl'lrough the contact 16 from terminal 95, line 96, switch 97 lines 98, 21, resistance: 20, line 19 from the supply line 18. These connections accordingly reverse the phases at this torque motor 7 and in the event the normal gravity throw out fails, they elfect a rocking of the shaft 7 9 positively out of high speed position for opening the high speed switch 82 and simultaneously close the low speed switch 63. This reversal of the motor 74, while still connected up for the original high speed throw thereof, is brought about due to the resistances 20, 46, being in parallel with this motor 74, and the direct connections being predominate. There is accordingly herein a simple safety device insuring that any throwing of the controller 15 into reverse position during operation of the motor 9 at high speed only effects cutting out of the high, speed operation of the motor. Thereafter, as the motor 9 is slowed down below a predetermined speed, the circuits through the contacts 89 and 92 are automatically opened by the governor 11, and circuits through the controller 15 and the resistances 20 and 46 become effective in energizing the direction switch motor 52 in the opposite direction, whereby the direction switch is actuated to close the circuit in a reverse direc tion through the low speed winding of the motor 9, and the motor 74 is subsequently actuated to switch the power circuit to the high speed winding of the motor 9.

To simplify the disclosure herein there has been omitted the acceleration resistances and their control. These may be connected to be operated by a torque motor from the lines extending to the low speed winding for the low speed acceleration torque motor, and from the lines to the high speed windings f or the high sped torque motor. The resistances for these accelerations may be brought out from the junction of these speed windings for the motor.

That is claimed and it is desired to secure by Letters Patent is 1. A reversible motor, a power supply therefor, switches in said supply, electric actuating means for the switches, a controller for the actuating means, resistance between the controller and the supply, and power supply connections by-passing the controller and rcsi, nce and adapted under certain conditions to be temporarily connected to said actuating means reversely to the connections tln'ough said resistance, whereby the last mentioned connections are rendered ,tem orarily ineffective.

2. A reversible motor, a power supply therefor, main and direction switches in said supply, electric actuating means for the main switches, additional electric actuating means for the direction switches, a controller provided with connections therefrom co-acting for reversing the motor operation, resistance between the controller and the supply, and power line connections by-passing said re. sistance and operable, when closed, to maintain the direction switch in original position after the connections through resistance to the direction actuating means have been reversed.

8. A reversible motor, a power supply therefor, main and direction switches in said supply, electric actuating means for the main switches, additional electric actuating means for the direction switches, a controller for reversing the motor operation, a. resistance between the controller and the supply, and connections through the closed direction switch by-passing said resistance and operable, when said connections are closed, to maintain the direction switch in original position, even though the connections through resistance to the direction switch actuating means have been reversed.

4. A reversible motor, power supply lines leading thereto, switches in said lines, polyphase electric actuating means for said switches, a control for said actuating means, resistance in the lines between said supply and said controller, and means bypassing the controller and resistance and operable in the event that the controller is moved to a reverse position when the motor is operating above a predetermined speed, to temporarily prevent the setting of said switches in position for reverse operation of the motor until said motor slows down.

5. A reversible two-speed motor, power supply lines leading thereto, switches in said lines, polyphase electric actuating means for said switches, a controller for said actuating means, resistance in the lines between said supply and said controller, and means by passing the controller and resistance and ope able, in the event that the controller is moved to a reverse position when the motor is operating above a predetermined speed, to maintain the switches in position for low peed operation of the motor in the same direction, and operable after the motor has slowed down, to allow the setting of the switches for reverse operation without any further movement of the controller. 6. A reversible polyphase motor, a power supply therefor, switches in said supply, electric actuating means for the switches, a controller for the actuating means, resi-iitance between the controller and the supply, and power line connections by-passing said resistance and operable, when closed, under certain conditions to maintain the direction switch temporarily in its original position even though the connections through the resistance to the direction switch actuating means have been reversed.

7. A reversible motor, a power supply therefor, main and direction switches in said supply, electric actuating means for the main switches, additional electric actuating means for the direction switches, a controller for reversing the motor operation, a speed controlled device for holding a direction switch i when toe motor is operating at a determined speed, connections to the controller through said direction switch and speed controlled device placing said controller in circuit with said device for ellecting through reversal oi? the controller a POWOI connection insuring an opening of a main switch.

8. A reversible motor, a power supply theretor, main and direction switches in said supply, electric actuating means for the main switches, additional electric actuating means for tl c direction si v ches, a controller for ltlVGlSlllg the motor operation, resistance between the controller and the supply, a speed controlled device for holding a direction switch in when the motor is operating at a determined speed, a. connection to the controller through said direction switch and soeed controlled device bypassing said resistance and cos upon shitting the con.- troll or for motor re ersal to connect the main switch actuating means for a power connection insuring opening a main switch.

9. it reversible motor, a polyphase alternating electric current supply therefor, main and direction switches for the motor, a polyphase actuating device for the main switches, an additional polyphase actuating device for the direction switches, a controller, a speed controlled device bypassing the conholler :lior holding the direction switch in at a dotern'iined speed of the motor, and connectioi'is from the controller as thrown for reversing the directioi'i of the motor to connect die power supply through the speed controlled device for operating the main switch actuating device for a power connection insnri opening a main switch.

it). A mi. speed reversiblemotor, a polyphase alternating current supply there'lior, "Htlll and direction switches for the motor, a torque motor for operating the main swil' hos and having a plurality of current pha. thereto, an additional torque motor I opera the direction switches, a con iroller, a speed controlled device provided u ith connections in a plmrality of phases of i@ t rection switch torque motor for bypassing the controller ilor holding the diroction switch in at a determined speed ol? the motor, and connections from the controller when thrown for reversing the direction ot' the motor travel for connecting the main switch torque motor in circuit with the controller for positively operating said motor for insuring o icning a main switch.

ll. 1'3. nnilti-speed reversiliile motor, a polyphase alternating current supply therefor, main and direction switches :tor the motor, a torque lflOlZOl. for operating the main switches and having a plurality of current phases memes thereto, an additional torque motor for operating the direction switches, a controller, resistances in a plurality of phases between said supply and controller, a speed con trolled device provided with connections in a plurality of phases of the direction switch torque motor for bypassing the controller for holding the direction switch in at a determined speed of the motor, and connections -from the controller, when thrown for reversing the directionot the motor travel, for connecting the main switch torque motor in circuit with the controller for positively operating said motor :for insuring opening a main switch.

12-. i'in electric control installation embodying low and high speed main switches, said low speed switch being normally closed, a polyphaso torque motor for actuating said switches, and a controller provided with connections in circuit with the torque motor operable normally for single direction 0poration of said motor for all positions of the controller and operable under predetermined operating conditions to reverse said motor.

13. An electric control installation embodyin main switches, a controller, a torque motor normally operable in one direction only, for actuating one oi said switches, said controller being provided with connections For placing said torque motor in circuit with said controller, under predetermined operating conditions, in such a way as to ellect reversal ot said torque motor for opening said last mentioned switch.

14-. A control installation embodying main high and low speed switches, a first torque motor therefor, direction switches, a second torque motor therefor, a reversible motor to be operated from said switches, a controller,

power supply means, connections from the controller and power supply means normally eli'ectivo in one direction of shifting the controller for operating said first torque motor in one direction and said second torque motor inone direction, connections normally ell'ective in the other direction of shifting of the controller for tending to operate the first torque motor in said one direction only and for oppositely operating the second torque motor, and additional connections effective upon reversal of the controller with the reversible motor still rotating above a predetermined seed precluding reversal of the second torque motor and etl'ecting reversal of the first torque motor.

15. In an electric elevator installationhaving low speed and high speed circuits, switches controlling the. energization ol'said circuits, a motor operrt ng said switches and a car-switch controlling said switch motor, connections whereby movement of the ar-switch from high speed position for one direction of the elevator travel to high speed position for the other direction of the elevator travel, when the elevator is traveling in the first said direction at a speed as great as a predetermined minimum, reverses the current to said switch motor and causes the same to positively switch the current from the high speed circuit to the low speed cireuit.

16. In an electric elevator installation having low speed and high speed circuits, switches controlling the energization of said circuits, a motor operating said switches and a car-switch controlling said switch motor, connections whereby movement of the car switch from high speed position for one direction of the elevator travel to high speed position for the other direction of the eleator travel, when the elevator is traveling in the first said direction at a speed as great as a predetermined minimum, reverses the current to said switch motor and causes the same to positively switch the current from the high speed circuit to the low speed circuit, and speed-controlled means preventing the energization of said switch motor in the direction to energize the high speed circuit in the reverse direction until a predetermined low speed has been attained.

In witness whereof I afiix my signature.

ERNEST B. THURSTON.

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