US1100134A - Controller. - Google Patents

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US1100134A
US1100134A US52985009A US1909529850A US1100134A US 1100134 A US1100134 A US 1100134A US 52985009 A US52985009 A US 52985009A US 1909529850 A US1909529850 A US 1909529850A US 1100134 A US1100134 A US 1100134A
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switch
wire
switches
circuit
resistance
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US52985009A
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Carl A Jacobson
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Kaestner & Hecht Co
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Kaestner & Hecht Co
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P7/00Arrangements for regulating or controlling the speed or torque of electric DC motors
    • H02P7/03Arrangements for regulating or controlling the speed or torque of electric DC motors for controlling the direction of rotation of DC motors

Description

G. A. JAGOBSON.
CONTROLLER.
APPLIOATION FILED NOV. 26, 1909.
Patented June 16, 1914.
2 SHIIETSSHBET 1.
ZN Z 4 Q5 w lssas O. A. JAOOBSON.
CONTROLLER.
APPLICATION FILED NOV. 26, 1909.
Patented June 16, 1914.
0 6 z w r v m W 0 n 1 H m h H T m m 7/0 wiav x- W 6631?! c acosoza. in 23W UNITED STATES PATENT OFFICE.
CARL A. JACOBSON, OF CHICAGO, ILLINOIS, ASSIGNOR T0 KAESTNER & HECH'I. COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.
CONTROLLER.
Specification of Letters Patent.
Patented June 16, 1914.
Application filed November 26, 1909. Serial No. 529,850.
To all whom it may concern:
Be it known that I, CARL ALRIK J ACOB- so: a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Controllers, of which th following is a specification.
This invention relates to apparatus for starting, stopping and reversing electric motors, the apparatus being arranged so that the current is gradually impressed upon the motor when starting or reversing.
The present embodiment is especially designed for use in connection with motors which must be frequently started, stopped and reversed, such as the motors of electrically-driven elevators.
In the accompanying drawings, Figure 1 is an elevation of a controller embodying the features of my invention, the electrical connections being indicated diagrammatically. Fig. 2 is a detail view of one of the switches comprised in the controller. Fig. 3 is a view of another form of switch employed in the controller. Fig. 1 is a fragmental sectional detail of still another form of switch used in the controller. Figs. 5 and 6 are fragmental detail views of the means for operating certain of the switches.
The controller comprises two switches A and B which control the circuit for operating the motor in one direction, say, in the forward directiom-two switches C and D controlling the circuit for operating the inotor in a reverse direction; a switch E which controls the circuits by means of which the switches A B C D are operated; switches ir H J by means of which resistance is cut into and out of the motor circuits; a solenoid for operating switches E F G H J K; and. a switch K for cutting resistance into and out of the solenoid circuit. All of the switches are preferably suitably supported upon a slab L of slate. marble. or other suitable insulating material.
The construction of the switchv A is illustrated in'Fig. 2. Said switch comprises an arm 1 which is pivoted at 2 to a bracket 3 fixed to the slab L. Said armcarries contacts 4 and 5 arranged to engage contacts '6 and 7, respectively, mounted upon the slab. The contacts are preferably formed of carbon. Preferably one pair of contacts is yielding. I have herein shown the contacts 4L and 5 as being slidably mounted in sleeves S on the arm 1 and as being connected by a' bridge or yoke 9. Fixed-to the yoke. 9 is a pin 10 extending loosely through thearni 1, a coiled spring 11 surrounding said pin and bearing against the adjusting nut 12 and the arm 1. Said spring tends to move the yoke to hold the contacts 4 and 5 forward, as shown in Fig. 2. Conducting strips 13 serve to insure good electrical connection between the contacts and the bracket Upon the slab L is mounted a contact 14 herein shown as yieldable, which contact is arranged to be engaged by the arm 1. Gravity, in this instance, is depended upon to swing the arm 1 in the direction to separate the contacts. Said arm is swung in the opposite direction into circuit-closing position by means of an electromagnet 15 of which t e arm 1 forms the armature.
16 is a pin fixed with relation to the bracket 3 and extending loosely through the arm 1, said pin carrying an adjustable stop 17 for limiting the gravitating movement of the arm.
In order to lock the switch against accidental closing movement I provide a detent 18 pivoted at 19 and adapted to lie in the path of the closing movement of the arm. A spring 20 tends to hold the detent 18 in operative position. The detent is arranged to be moved into inoperative position by the electromagnet 15.
The switch B is similar in construction to the switch A, except that there are no 0011- tacts corresponding to the contacts 5, 7 and 14. The switches C and D are similar in construction to-the switches B and A, respectively. v I
The general construction of the swltches F G H J K is shown in Fig. 3. Each of said switches comprises an arm 21 pivoted at 22 and carrying two yielding contacts 23 and 24 arranged to coiiperate with con tacts 25 and 26, respectively, upon the slab L. Conducting strips 27, 28 and 29 insure good electrical communication betwe the contacts 23 and 24 and the brackets 30. The arrangement of the contacts is such that the contacts 24 26 will meet and close a circuit before the contacts 23 25 come into engagement with each other.
, The switch E is generally similar to the switches F G H J K, the switch E, however, having in place of the contacts 24 and 26, the contacts shown in Fig. 4. The contact 31 is carried by'the arm 21, and the contacts 32, 33, 34 are mounted on theslab and are adapted to come in contact with each other when the arm 21 is swung to close the switch.
The switches A B C D are electrically operated by means of the electromagnets 15, while the switches E F G H J K in this instance are mechanically operated. In the embodiment herein shown, the means for operating the switches E F G H J K comprises a rock shaft 35 having fixed thereon cams Each of said cams is arranged to bear upon a suitable portion of or a part carried by an arm 21, as an antifriction roller 42. The cams are so fixed upon the shaft that the cams 36 and 41'will hold their switches E and K closed when the switches F G H J v are open, and so that when the shaft is rocked the switches will be operated in the following order: The
switch E is opened, the switches F G H J closed successively in the order in which they are named, and the switch K opened. The shaft 35 occupies the same position in Figs. 3 and 6 that it does in Fig. 5. In Figs. 3' and 6 I have indicated in dotted lines the rclative positions of the high points of the cams.
The cam shaft 35 is arranged to be rocked by means herein shown as a solenoid 43 comprising a coil 44 and a core 45, said core being suitably connected to the shaft, as by a forked arm 46. In order to retard or cushion the movements of the core 45 a dashpot 47 of any preferred construction may be provided. I
A resistance 48 of any suitable construction is arranged to be included in the motor circuit at times by a wire 48 leading to the contact 25 of the switch F; a wire49 leading to the contact 26 of the switch G; a wire 50- connected to the contact 25 of the switch G; a wire 51 connected to the contact 26 of the switch H; a wire 52 connected to the contact 25 of the switch H; a wire 53 attached to the contact 26 of the switch J; and a wire 54 leading to the contact 25 of the switch J. The wires 48 to 54 are so attached to the resistance that various portions of the resistance will beincluded in the circuit, depending upon which wire carries the current, wire 48 including all of the resistance, and wires 49 50, 51, 52 and 53 including progressively less amounts of resistance. A suitable circuit-opener and closer located at any preferred point, is indicated diagrammatically at 55, the movable switch member 56 being adapted to engage the relatively stationary contacts 57 58.
When the controller is used in connection followin with elevator motors, the switch 55 will be located on the elevator car, said switch being arranged for manual actuation by the operator in the car. The movable contact member 56 is connected to the line switch 59 or other suitable source of electrical energy by a wire 60, said wire being connected with the brackets 30 of the switches F G H J K as indicated in Fig. 1. The contact member 57 is connected to the electromagnet 15 of the switch C by a wire 61. The electromagnets of the switches C and D are connected by a wire 62, and the electromagnet of the switch D is connected to one of the contacts 32 33 34 of the switch E, say, the contact 32, by a wire 63. The contact 58 of the switch 55 is connected to the electromagnet 15 of the switch B by a wire 64. The electromagnets 15 of the switches A and B are connected by a wire 65, the electromagnet of the switch A being connected to the contact 33 of the switch E by a wire 66. The motor is indicated at 67, and an electrical means for braking the motor to stop it promptly is diagrammatically represented at 68.
When the switch member 56 occupies an intermediate position the motor circuit is interrupted and the motor is at rest, switches E and K being closed and all the other switches A B C D F G H J being open. When the switch member 56 is moved into engagement with the contact 58, the following circuit is closed: line switch 59, wire 71, contact 6 of switch A, wire 70, contact 6 of switch D, wire 69, contact 34 of switch E, contact 33 of switch E, wire 66, electromagnet 15 of switch A, wire 65, electromagnet 15 of switch B, wire 64, contact 58, switch member 56, and wire 60 to line switch 59. The electromagnets of the switches A B are thus energized, closing said switches, and thereby establishing the following circuit: line switch 59, wire 71, contacts 6 and 4 of switchA, the arm 1 of said switch, contacts 5 and 7 of said switch, wire 72, solenoid coil 44, wire 73, contact 26 of switch K, contact 24 of switch K, arm 21 of said switch, bracket 30 of switch K, and wire 60 to line switch 59. The solenoid 43 is thereby energized and the shaft 35 rocked. The first one of the shaft-controlled switches to be operated is the switch E, which switch is opened, thereby separating the contacts 33 34. The circuit of the electromagnets 15 of the switches A B, however, is not thereby broken, for said electromagnets are connected by the wire 75 to the contact 14 of .the switch A, and the current flows through the path: line switch 59, wire 71, switch wire 75, electromagnet 15 of switch A, wire 65, electromagnet 15 of switch B, wire 64, cont-act 58, switch member 56, wire 60, to line switch59.
The second shafbcontrolled switch to be .78, wire 79, bracket 3 and arm 1 of switch B, contacts 4 and 6 of switch B, wire 80, contact 6 of switch 0, wire 81, Wire 54, the
entire resistance 48, wire 48*, contacts 25' and 23 of switch F, arm 21 and bracket 30 of switch F, wire 60 to line switch 59. The motor 67 is thereby placed in operation. The next switch to be operated is that formed by the contacts 24 26 of switch G, which contacts close before the contacts 23 25 are placed in engagement with each other. hen the contacts 24 26 close, the current flows through wire 49, contacts 26 24 and arm 21 of switch. G instead of through the resistance between wires 49 and 48. wire 48 switch. F, and said resistance thereby being cut out of the motor circuit. Similarly when the contacts 23 25 of switch G close, the current flows through wire 50 instead of through wire 4-9, thereby cutting out still more resistance. This switch,H, the next one to be operated,in like manner cuts out, in succession, two portions of the resistance 48. The next switch to be operated,switch J ,first closes a circuit through wire 53 and contacts 26 24 and arm 21 of said switch, and then closes a shunt around the resistance 48 as follows: wire 81, contacts 25 23, arm 21 and bracket 30 of switch J and wire 60. The next and last switch to be operated is the switch K, said switch being opened. The apparatus will now be in the condition shown in Fig. 1, the live circuits being indicated by heavy lines, and the dead circuits by light lines.
The means by which the brake is operated to release the motor for operation may now be considered. To illustrate the method of operation the part 68 may be assumed to be an elect-romag'net which, when energized, rcleases the brake. One terminal of the winding for said electromagnet is connected to the contact 25 of the switch K by a wire 82, and said contact is connected through the resistance 83 to the bracket 30 of said switch K. The other terminal of the magnetwinding is connected to contact 7 of switch D by a wire 84, said contact being connected to the corresponding contact of the switch A by a wire 85. When the switch member 56 is placed in engagement with the contact 58 and the switch A closed, the following circuit through the electromagnet 68 is established: line switch 59, wire 71, contacts 6 and 4 of switch A, arm 1 of said. switch,
contacts 5 and 7 of said switch, wire 85, contact 7 of switch D, wire 84, magnet 68, wire 82, contacts 25 and 23 of switch K, arm 21 and bracket 30 of said switch K, and wire 60 to line switch 59.
The electromagnet 68 is thereby energized to release-the brake. When the switch K is finally opened, the brake circuit is still maintained through the resistance 83. 26 and bracket 30 of switch K are connected by a resistance 74, which remains in series with the. solenoid coil 43 when the switch K is opened. When the circuit-closer is placed in open position, all the circuits are broken, the electromagnets denergized, the brake applied to the motor, and the shaft 35 turned by the gravitating movement of the core 45. into the position it is shown to occupy in Figs. 3, 5 and 6.
\Vhen it is desired to reverse the direction of rotation of the motor, the switch member 56 is placed in e agement with the contact 57, thereby closing the following circuit: line switch 59, wire 71, contact '6 of the switch A, wire 70, contact 6 of the switch D, wire 69, contacts 34, 33 and 32 of switch E, wire 63, electromagnet 15 of switch D, wire 62, electromagnet 15 of switch C, wire 61, contact 57, switch member 56, wire and line switch 59. The 'electroma'gnets of the switches C D are thus energized, ciosing said switches and thereby establishing the following circuit: line switch 59, wire 71, contact 6 of switch A, wire 70, contacts 6 and 4 of switch D, arm 1 of switch D, contacts 5 and 7 of switch D, wire 85, contact 7 of switch A, wire 72, s'oienoid 44, wire 73, contact 26 of switch K, contact 24 of switch K, arm 21 of said switch, bracket 3061? switch K, and wire 60 to line switch 59 The solenoid '43 is thereby energized, and the switches E F G H J K 'o-peratedas before described. The wire 86 serves a purpose similar to that ofwire 75. The current path closed through the motor by the cooperative action of the switches D and J may be traced as follows: line switch 59, wire 71, wire 70, switch D, wire 78, motor 67, wire 7 7, switch C,.wire 81, switch J, wire 60, to line switch 59.
It will be seen that wheh the circuits hereinbefore described have been broken, as at 56, they cannot again be closed except through the switch E. If, there-fore, the core of th'e'solenoi'd 43 should fail to come down after the switch 56 is opened, the closin'gi of said switch on either side will not start the motor because the starting circuits for all of the electromagnets 15 are open at l, and the switches A B or C D therefore cannot beclosed. The switch E is closed only when the core of the solenoid 43 is in its lowermost position and, as is apparent, the motor therefore cannot be started unless all of the resistance 48 is in the motor circuit.
It will be understood that the motor may be of any ordinary or preferred construction. The function of the switch K is to cut in and out the resistances 74 "and 8-3, more 0 its current being required initially to operate the solenoid a3 and the electromagnet 68 than to hold the switches E F G H J K in the position shown in Fig. 1 and to hold the brake in the release position. Blow-out coils 87 may be provided, if desired, and may be connected in circuit in any suitable manner.
I would have it understood that the invention is not limited to the details hereinset forth, for various modifications will occur to those skilled in the art.
I claim as my invention:
1. In a motor controller, in combination, two circuits each including two electromagnets, a switch for opening and closing either of said circuits, two reversing switches associated with each of said circuits on opposite sides of the motor, each pair of said switches being arranged to be closed by a pair of said electromagnets, the respective pairs of said switches being arranged .to connect up the motor in their circuits to run in opposite directions, a resistance arranged to be included in circuit with the motor, a series of switches connected to said resistance and adapted to gradually cut out the resistance from the motor circuit, a solenoid and connections for successively operating said switches, and a circuit through said solenoid adapted to be closed by either of the two pairs of reversing switches. D
2. In a motor controller, in combination, two circuits each including two electromagnets, a switch for opening and closing either of said circuits, two reversing switches associated with each of said circuits on opposite sides of the motor, each pair of said switches being arranged to be closed by a pair of sa d electromagnets, the respective palrs of said switches being arranged to connect up the motor in their circuits to run in opposite d1- rections, a brake magnet adapted to be operated upon the closing of either of the two pairs of reversin switches, a resistance arranged to be included in circuit with the motor, a plurality of swltches connected to said resistance and arranged to gradually cut out portions thereof from the motor circuit, a cam shaft for successively operating said switches, and a solenoid arranged to rock said cam shaft, said solenoid being included in a circuit which is completed by the closing of either of the two pairs of reversing switches.
3. The combination of a load circuit: a resistance in said circuit; a series of switches connected to said resistance and adapted to cut out portions thereof; a solenoid and connections for successively operating said switches; a circuit including said solenoid; a brake-operating electromagnet; a circuit including said brake magnet; a second and a third resistance; and a switch operable by said solenoid for insertin said second and third resistances in the so enoid circuit and the brake magnet circuit respectively after all of the first mentioned switches have been operated.
4. In a controller, the combination of a switch controlling the supply of current to the load, electromagnetic means for closing said switch, a resistance, means for" cutting said resistance into and out of the load circuit, means normally lying in position to obstruct the closing movement of said switch, said obstructing means being withdrawable from operative position by said electromagnetic means when the latter is energized, and means acting to prevent energizing of said electromagnetic means until said resistance is included in the load circuit.
5. In a controller, the combination of a switch controlling the supply of current to the load, a resistance, a solenoid, means actuated by said solenoid for cutting said resistance into and out of the-load circuit, and means movable into position to obstruct the closing of said switch when the parts of said solenoid have failed to resume their normal position upon the breaking of the solenoid circuit.
6. In a controller, the combination of a switch controlling the flow of current to the load, a resistance, means for cutting said resistance into and out of the load circuit, a detent preventing said switch from closing until said resistance is included in the load circuit, and electromagnetic means for closing said switch and withdrawing said detent from operative position, the last mentioned means being under the control of said resistance cutting means.
7. In a controller, the combination of a switch controlling the flow of current to the load, an electromagnet for closing said switch, a resistance, a solenoid, means actuated by said solenoid for cuttin said resistance into and out of the load circuit, and a detent actuated by said electromagnet when the latter is energized, but normally preventing said switch from closing when the parts of said solenoid have failed to resume their normal position with all of said resistance cut into the load circuit.
8. The combination of two parallel circuits each having a pair of electromagnets therein: a manually-operated switch for alternately closing said circuits; two motor circuits for driving a motor in opposite di rections; two switches in each of said motor circuits at opposite sides of the motor, the last mentioned switches being operable by said electromagnets to alternately close. said motor circuits; a switch E adapted to break both of the first mentioned circuits, the first mentioned switches closing circuits through said electromagnets: a resistance; a series of switches for cutting said resistance into and out of the motor circuit; and
a solenoid and connections for opening the switch E and successively closing said series of switches, the switch E being held open when all of said resistance has been cut out.
9. In a controller, the combination of an electric circuit; a resistance connected with said circuit; a series of switches each carrying a plurality of pairs of contacts, one contact of each pair being connected to a point along said resistance and the other contact being connected to said circuit; and means for successively operating said switches to gradually cut said resistance out of said circuit, the pairs of contacts of said switches meeting one at a time.
10. In a controller for elevator motors, in combination, a switch controlling the flow of current to the motor, an electromagnet for operating said switch, a switch adapted to close a circuit through said electromagnet, amanually operated switch for opening and closing said circuit, the first mentioned switch being adapted to close a circuit through said electromagnet, aresistance, and a solenoid and connections for cutting said resistance into and out of the motor circuit, said connections being adapted to open the second mentioned switch, said switch being held open when all of said resistance has been cut out.
11. In a controller, in combination, a switch controlling the flow of current to the load, electromagnetic means for closing said switch, said switch being arranged to close a circuit through said means, a hand switch adapted to open and close said circuit, a third switch in said circuit, a resistance, a plurality of switches for cutting said resistance into and out of series with the load, a cam shaft for operating said. plurality of switches and said third switch, said cam shaft being adapted to first open said third switch and then successively close said plurality of switches for cutting said resistance out of the load circuit.
12. In a motor controller, in combination, two circuits each including an electromagnet, a switch for opening and closing said circuits alternately, a second switch adapted to open and close both of said circuits, and two switches operable by said electroma nets and adapted to close circuits throng themotor to run it in op osite directions, the latter switches when clbsed leading the current directly through them and through said electromagnets to short circuit the second mentioned switch, the latter being opened upon the closing of either of said two switches.
13. The combination of two parallel circuits each having a pair of electromagnets therein; a manually-operated switch for alternately closing said circuits; two motor circuits for driving a motor in opposite directions; a pair of reversing switches in each of said motor circuits at opposite sides of the motor, said reversing switchesbeinlg operable by said electroma-gnets; a switch adapted to break both of the first mentioned circuits, the said reversing switches adapted to close circuits through said electromagnets; a resistance; aseries of switches for cutting portions of said resistance into and out of said motor circult; and a solenoid and connections for opening the switch E and successively closing said series of switches, the switch E being held open when any portion of said resistance is cut out. p
14. In a controller, in combination, a reversing switch; electromagnetic means for closing said switch; a hand switch adapted to open and close the operating circuit of said electromagnetic means; a third switch in said circuit; a resistance; a plurality of switches for cutting said reslstance into and out of series with the load; and a cam shaft for operating said plurality-of switches and said third switch, said cam shaft bem adapted to first open said third switch an then successively close said plurality of switches for cutting out said resistance.
CARL A. J AGOBSON.
Witnesses:
E. F. Hmm'r, R. Burma
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814691A (en) * 1951-03-08 1957-11-26 Brandt & Fils Device for locking movable parts, notably relay armatures
US2916677A (en) * 1957-02-21 1959-12-08 Westinghouse Air Brake Co Armature hold-down latch for electrical relays
US2929002A (en) * 1956-05-09 1960-03-15 Allis Chalmers Mfg Co Magnetically actuated mechanical interlock
US3068379A (en) * 1957-04-11 1962-12-11 Fed Pacific Electric Co Circuit protective apparatus
DE1219114B (en) * 1963-08-30 1966-06-16 Siemens Ag Cam switching element
US3448420A (en) * 1965-10-22 1969-06-03 Warco Ind Inc Safety lock for electrically operated relays

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814691A (en) * 1951-03-08 1957-11-26 Brandt & Fils Device for locking movable parts, notably relay armatures
US2929002A (en) * 1956-05-09 1960-03-15 Allis Chalmers Mfg Co Magnetically actuated mechanical interlock
US2916677A (en) * 1957-02-21 1959-12-08 Westinghouse Air Brake Co Armature hold-down latch for electrical relays
US3068379A (en) * 1957-04-11 1962-12-11 Fed Pacific Electric Co Circuit protective apparatus
DE1219114B (en) * 1963-08-30 1966-06-16 Siemens Ag Cam switching element
US3448420A (en) * 1965-10-22 1969-06-03 Warco Ind Inc Safety lock for electrically operated relays

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