US872349A - Motor-controlling system. - Google Patents

Description

PATENTED DEG. 3, 1907.

J. D. IHLDER. MOTOR GONTROLLING SYSTEM.

APPLICATION FILED JULY 28,1905.

WITNESSES:

UNITED STATES PATENT OFFICE.

JOHN n. IHL'DEE, OF NEW YORK, N. Y., ASSIGNOE To O'rrs ELEVATOE COMPANY, or JERSEY crrY, NEW JERSEY, A cOErOEATIoN OE NEW JERSEY.

MOTOR-CONTROLLING BYBTEH.

,and useful Improvement in Motor-Controlling Systems, of which the, following is a specificatio'i.

My invention relates to im rovements inA motor-controlling systems am is adapted to the operation of electric motors in general but is particularly applicable to those use d forvhoisting purposes 1n which the motor 1s freguently started, sto ped and reversed.

ne of the objects o my invention is the provision of a simple and efficient means for reventinr current from passing through oth 'of t e motor-reversing means Shoud the circuits kto the latter become deranged.

Another object of my invention is to automatically stop the motor should the circuits be thus deran ed.

'A further object o rn invention is the provision of a simplifie ,construction for preventi'n excessive speed of the motor.

Other O jects of this invention Wlll appear hereinafter.

My invention consists of the ap aratus, circuits and connections hereina ter de scribed, the novel combinations being pointed out in the claims.

The accompanyin drawi v illustrates my invention as applie to an e ectric hoisting or elevator system including a car C havin a manually o erable Switch O which is use to control t e starting, stopping and rel versing of the hoisting motor M.

R and R are the reversing switches which determine the direction of rotation of the motor-armature. d

T designates a number of small switches which are for the u ose ofl automatically slowing down and Fnsi-liv sto` g the car at the upper and lower liniits ol) its travel.

D and E are magnetic switches which operate to revent the motor M from reachmg too hig a spoed.

H. is a magnetic switch which operates in conjunction with the load magnet" L to 60. automaticall\' slow down the eleva`tor at the desired landing to an amount proportional to the load.

S 'and F are magnetic switches used to P'QSIUC@ speed changes.

Specication of Lettera Patent.' Application led 1111128.1905. Serial lo: 271.585-

Patented Dec. 3, 1007.

A designates what I call an accelerating magnet which o erates contacts controlling the insertion an cuttingl out of the starting resistance and series fiel 51. y

P designates a potential or safety switch which Serves to connect the Sourcel of -current supply and to the system..

B is a safet magnetic switch and' its duty is to prevent oth of the magnet coils of the reversing switches R and' R from receivin current at the same time as this would ten to destroy their proper o eration.

The potential switch is shown in its closed position, that is, the sup ly mains and are connected to the wires 2 and 3, respectively. The switch is held lin this position against the action of a spring`by the magnet coil 1 which receives current at the full line potential being connected through the normally closed contacts Of the magnet B to the positive and negative mains.

The manually operable `switch O cornprises a contact segment 12 adapted to be moved into engagement with the fixed oontacts 4, 5,. 6 and 7 when moved by the handle 13 in one directionand into engagement with the contacts 8, 9, 10 and 11 whenV -one or the other of the contacts 7 and 11, pending on which Wa the segment is moved, 4to the potential switc 15 lwhich is connected to the supply main by one of the arms of switch P. a

In order ,to understand the operation of my system, let'the handle 13 of switch O be moved to the left until the segment'12 engages the fixed contact 4. This will connect the negative Wire 14 to the lower terminal of the magnet H through the contacts of sto motion switch T lwhich are connected by t e bri 'ng piece 16, the other terminal of magnet being connected by the wire 17 to the movable contacts 18, 19, 20 and 21 of the reversing switches, av circuit to the positive wire 2 bei open at these reversing switch contacts. he segment 12 of switch O is now moved until it engages the fixed contact 5 when a circuit will be established from the negative wire 14 by theI bridging iece 22 of switch T to the magnet ooil, 23 o reversing switch R, the other terminal of this ooi1,23

being connected through the coil 24 ofswitch Thus it will be seen that a circuit haspbeen established from the positive to the negative main through the magnet 23 and coil 24 of the safety switch B.

The motor starting or reversing switches R and R each comprises a ma netic core or plunger to which are fastene yinsulated pieces carrying contact-s suchas 18, 19, 20, etc. In the path of these movable contacts are fixed contacts such as 34, 36 and 3 7 which are adapted'to be engaged by them. The coil 23 of switch R, when energized, tends to raise its core to which are fastened the contacts 31, 32, 18 and 19 in an upward direction causing the-contacts 18 and 19 tov engage the iixed contacts directly above, that is, 34, 35, and 36, respectively. The mov- 'able contacts 31 and 32 will at the same time be moved away from the ixed contacts 30 and 33, respectively. The coil 29,'however, tends when excited to pull the core and its contacts iny a downward direction. switches R and R have a rocker arm which is fastened by a pin on each core of the respective switches and operates to prevent both switches being in their extreme upward or downward-.positions at the same time. This interlocking device may be as shownon the drawing, or it may be such 'as shown in the Patent No. 704,336, franted me on July 8, 1902, wherein a pair el? reversing switches is shown and described whose construction is similar tothe switches R and R of the present case.

As shown hereinbefore, when the segment 12 of the switch() is moved so as to energize the contact 5, a circuit is established' through.

the reversing switch coil'23 and the coil 24 of magnet switch B. The ma net 23 will cause the .contact 18 to engage t e fixed contacts 34 and 35, and also tue contact 19 to engage the`contact'36 and by means of the rocker arm or interlocking device between the switchesR and R', the contacts 39 and 40 will engage the fixed contacts 4 1 and 42, rep

spectively.

The magnetic switch B, it will be noticed,

has two coils 24 and 43. Each of these coils is in series with one of thecoils 23and 27 of the reversing switches .R and R', respectively. The coils 24 and 43 are so wound that when `one lcoil alone is ener ized it has not suflieient strength to cause t e contacts 69 of switch B to become disconnected. Should, however, both coils 24 and 43 receive current at the same time the magnet coils 23 and 27 of the switches R and R would also receive current andinake the operation of the reversingswitches very uncertain. The

coils 24,and-43'- are Wound cumulatively, thatf is, one assists theother when both are energized, and when co-acting with .'eachother they have sufficient strength to separate the contacts 69. Since these contacts include a circuit through the wires 80, 81, to the hold- The and 42, respectively.

l ing coil of the potential switch P, their becoming separated will cause coil 1 tobe deenergized, thereby causingl the potential switch arms to drop, severing all connection between the motor controlling system and the source of-currentsupply. Thel circuit to the brake magnet 52 is broken at the contact,

15, thus causing the brake to be applied to I stop the motor and hoisting machinery-operated thereby.

When the potential 'switch magnet 1 becomes denergize'd, the contacts 66 will be closed by the dropping ofthe switch arm completing a circuit through the extra field 54 and a small portion of the load resistance 55 which is in series therewith.. 'lhe circuit thus formed is a local circuit including thev armature and may be traced from the brush 37 through contacts 41 and 39,' wire 44, armature resistance 45, wire 68, contacts 66, wire '67, that portion of the load resistance which is shown at 'the extreme left in the 54, wire 56, 'wire 17, contacts 40 and 42,

holding coil 28, to the armature brush 38.

A dynamic braking effect is thus 'produced to cause theniotor to speedily come to rest.- Whenthe coil 23 of reversing switch'R is energized, thecontact 18 engages .contacts l34, 35, and the contact 19 engages the contact 36. Substantially at thesame time the contacts 39 and 40 engage the contacts 41 circuit is 'thus closed to the magnet H'through the Wire 2, contacts 34, 18, and wire's 17 andi82. The magnet H is therefore energized and causes its contacts to separate, thus preventing the load magnet L from receiving any current.

When the switch R is operated, a circuit is closed also to the-magnet 28 from the posi` tive main through vthe'contacts 34, 18,'wire 17, and contacts 40, `42. The magnet 28 when energized exerts a downward pull on4v the core of the reversing switch magnet 27 insuring intimatecontact between the con# tacts 39, 41 and40, 42, respectively. The circuit through .the magnet 28 continuesto 'the brush 38, through armature M, brush 37, contacts 39, 41, and wire 44.to the startingl resistances45, 46, 47, 48, 49,-and 50', series field 51, to thenegative'or wire 3. The,

brake will also be raised out of en 'a errient,

being connected by contact 35 wit 't opositive line, and to the negative linby wire 1'4. `v

The motor is now free to start, .current'to the armature being limited, however', by' vthe starting resistance, 45, v46, etc. 'The series field 51 will also receive current. The-'shunt field designated by 53 being connected 'to wire 17 ono'ne side and 'wire 3 rmtheother' will be energized to its full strength receiving current Iat 'uli line potential.'

#The slow-s eed m netS 'being connected in shunt to acircuit comp rising the motorlarmature and theresistance 45 will not be accelerates. to slow speed, resulting in a :energized suiciently to close its contacts 7U since the differencefof potential across the terminals to which it is'connected is yat the,

momentof starting very low. l As the motor adually'increasing counter-electro-motive force,

.the magnet S is finally energized tothe pointwhere it will operate to c ose its contacts 70 which will result in connecting the extra field 54 having the load resistance 55 in series with it across the motor armature." One terminal orA the extra field 54 is connected to wire 17 and so on to the armature brush 38 and the right-hand end of the resistance55 is connected by Wires 56 ,and 44 which as before shown is connected to the armature brush 37. The extra field will now receive current -of'an amount depending upon the counter-electro-motive force of the revolving armature and therefore its speed.- The next operation of the system is-to move the lever 13 of switch O to its extreme left-hand position causing the segment 12 to engage the contact 6. N ow contact 6 is connected by the bridging piece 6 1 of switch 'l to the wire 62 and by means of the iiormally'closed contacts 76 of magnet switch D t'o wire 63,' the latter eeiiigconnected to one terniinai of the coil o'' fast-speed magnet F whose other terminal is connected by wire 17 to the posi-4 tive main. The fast speed magnet F is theretore connected across trie power mains.

and will at lonce operate to close the-contacts 64C and substantially at the saine time to open the contacts 65 This will be conducive totwo results: first, the separating of contacts 65 will open the circuit to the coil ofi.

slow speed magnet S causing it to separate its contacts and thus interrupt the circuit supplying the extra field by wire 44; second, the closing Voithe contacts 64 will shorty circuit thestarting resistance 45. The field strength of the motor having been weakened by opening the circuit ofthe eXtra field 54 the motor Will revolve at a faster speed. The resistance 45 havin been short'circuited by the magnet switch` the potential across the terminals of the accelerating magnet A, which are practicallv at this time across the motor armature will have risen to avalue sufficient to energize the magnet A. This magnet A has one terminal connected to the 'wire 17 which is at the same potential as the' motor-brush 3S, being connected to iti lts other terminal is connected through the contacts 58 and 59 by. wire 57 to apoint onthe soy starting resistance 46. y This magnet then is shunted across a circuit comprising the motor armature and the starting resistance 45 and a portion of resistance 46.

Asthe motor accelerates from rest the po-f' tential will rise in` thecoil of magnet Av which will result in operating the movablecontacts -of magnet A in succession in a well known way to cut out or yshort-circuit the starting resistance 45 inte the armature circuit. vincrease in armature resistance and in field resistances. The magnet A as shown controls seven movable contacts shown directly beneath it, and the first five o rate to cut out resistance only. The sixt places" the resistance 52 in parallel with the series field 51, and the seventh and last vcontact shortcircuits this resistance as well as the series field. The motor now runs at itsnormal full speed asV a shunt machine having its arma- .mal conditions it will be excited sufficiently to open its contacts 76 to interrupt a circuit supplying the fast speed magnet F, by Way of wires62- and 63, causing the switch F to become denergized and drop its plunger.

which would result in establishing a circuit to slow speed switch S and cause the latter to close a circuit to the extra field 54 through `the load resistance 55. At about the same time, the fast speed magnet F re-insertsthe ilie magnetism tiius produced wili cause the motor to at once slow down when the magnet D will again permit the contacts 76 to engage with each other. The safety magnet E is set to operate at a somewhat higher voltage than that required to operate magnet D so that vshould the potential across the motorarmaturereach a value 'high enough to operate magnet E, it will open its contacts '77, which maintain 'a circuit su 'plying the potential switchinagnet l and i y so doing allow. k the magnet l to become deenergized Iand interrupt the main line circuitaiigl also to'open the circuitsupplying the brake magnet 52. The operation of the safety' magnet E there- -fore breaks the current-supply to the motor and effects the application or the brake,A

while the motor and circuits act as a 'dynamic brake until the motor nas come to rest.

In order to show the normal method of stopping, such as making a landing, let it b e supposed that the motor has been brought to fu speed, the contact segment i2 of switch O being in en agement with four fixed contacts 7 4, 5 an 6. The'iirst step is to move the lever 13 until the contact segment 12moves out of engagement with the contact 6, This will open the circuit by wire 62 tothe switch- F, causing the same to operate to insert the resistance 45 inthe armature circuit and to energize the magnet of switch S, thereby energizing the extra field 54 ina manner which was clearly pointed out Yin connection with the operation of the sa'fet' -ma et D. -The motor now runs at a reducedgrsipeed. The

" segment 12 of switch C is next disengaged.'

from 'contact 5. This breaks thelcircuit to.

the magnet coil' 23 of the reversing switch R' causing it to drop, and as before 'stop the motor. Should, however, the lhandle of thel switch O be rapidly brought from its extreme or fastspeed position to its center otoff position, a circuit through wire '83 to the magnet H wouldin .this case belbroken at the switch contact 4. lThemagnet H would therefore be denergized anden closl ing its contact establish a circuit to the load struction .with the exception of the secondj one 60 .which is fastened to, but insulated from, a small contact 58 which contact is in engagement with a small fixed contact 59 when not raised'out of contact by 'the operation ofthe load magnet Ii. Should the-inotor be generating sufficient counter-electro-t motive force :during the period required to stop, the load magnet L, having been connected in circuit by the operation of the magi net switch Hwill raise the contact 60 causing the circuit which energized the accelerating magnet A to become broken through the wire 57. The acceleratin magnet will there-l forel drop its contacts. his would revent the operator from accelerating to full speed oncc more (since the circuit'to the accelerating ma et A is broken) until the contacts 58 and 59 ave again been brought into contact which would insure the starting resistance together with the series field being agaii'i included in the armature circuit, andl preventing current at the full line potential being thrown on the .motor until the extra field has been weakenedl by having the load resistance connected in series with fit.. A

The 'automatic lii'i'iitswitch T comprises two'sets of switches', euch' sethavingrthree. switchcs. Each switch is indicated or shown on the drawing as comprising two small contacts which arebridged by a metallic bridging piece such as 16 arid 6l. The upper set of three switches are operatedI byi some part ofthe hoisting machinery,oni'` set. of three operatng'sthe car approaches'the. upper limit of its travel; the other setfof three switches being similarly' operated` as 'the 'clar a' preaches the'l'ower limit 'of lits trave.

05- structed so as to operate successively, 'to pro- Yduce an automaticstog the saine, an additional e switches in each set are consimilar. to that produced4 by the switch when the llatter is brought from a full speed position to a stop or off osition b tions to t e switch v being led through the virtue of the connec- A saine-switche's. Therefore, should the operator leave the switch O in any of the running positions, lthe automatic 'switch would 'at the .limit of travelstop the machine..

' The operation o'the lreversing switch, R

l is brought about when it is desired to run the motor in a reverse direction, bymoving the handle 13 of the switch O in a right-handed direction causing the contacts 8', 9 and 10 to become energized. In this case the circuits through the switch C pass through the lower set o switches comprising the automatic switch T. AThe operations of the umts are similar to the previously described operation.l VA. circuit to magnet 'coil 27 asses through the coil 43 of-i'nagnet B while At e circuit ,to the inotor-arniature lpasses through coil 29. ofthe reversing switc R. The current passes through the niotor-armature in a reverse direction to what it .did iii the-former case, `roducing a reverse rotation of the -morent through the contact 37! instead. of contact-35 as before.

In reviewing the operation of the system as disclosed, it will be seen that the excessive .speed magnet switches -D and E provide for and effectually'prevent any.undue. increase,

in motor Vspeed which so frequentl is conducive to disastrous results. Also e safety which o crates at once to stop-the machine should t e reversing switch coils get ound- 'ed on one another, or should both of t e magnet coils which operate the reversing switches Rand R receive current at the same time,

from whatever cause, the machine is at once brought to rest. v

Without limiting myself tothe precise 'construction of details or arra ment of parts herein shown and describe but reserving,

spirit the right .to vary the samewithin the and scope of my invention what Iclaim and 'desire to have protected is' I. The combination with a pair of reversingswitches, of electroni nets for actuating 'the same, an additionai e ectroma et, an ineans'controlled by said additioiiaelectromagnet for reventing v.the operation of both of saidswitc ies at the same time.

2. The combination with a pair of reversing switches, of clectromag :ietsv for operating e octromagnetl hav- 'inglcoils 1n seriesiwith the aforesaid Aelectromagnets', and means controlled by said addi- 9. The combination with a plurality. of switches, of eleetroinagnets for operating iw Letters Patent.

heibrake magnet is now fed with cur- ,tional electromagnet for insuring theop'era- 'tion' of only'one o'fsaid switches at a time.

io'0 magnet switch-.B with its double magnet coil j said switches,l an additional electroni net having coils wound to assist one anot er,

-said coils being in series with the first-named clectromagnets, and means operated upon the energization of more than one coil of said additional electroniagnet for preventing the operation of more than one switch at a time.

4. The'conibinatiori with a motor, of electric motor-controlling means, reversing switches, magnets for operating said switches, a circuit-breaker, and means for operating said circuit-breaker to cause the 'stopping of the motor upon bothof said magnets receiving current at the same time.

5. The combination with a motor, of controllin means therefor, circuits and connections or said-motor and motor-controlling' means, reversii v switches, ma nets for operating said switc ies, a potcntia switch in the main line circuit, and means co-aeting with said niotor-controlling-means and magnets for operating said, potential switch to interrupt the mainline circuit upon both of said magnets receiving current at the saine time.

6. The combination with a motor, of reversing switches therefor, electromagnets for operating said switches, a safety magnet having coils respectively in series with the first-named electromagnets, and means Kcontrolled by said safety magnet for interrupting the circuit to the motor upon encrgization of both coils of said safety magnet.

7. The combination with a motor, of inotor-controlling-means comprising reversing switches, electromagnets for. operating said switches, a safety magnet having coils respectively in series with the aforesaid electromagnets, and means for interrupting the circuit to said motor-controlling-means operated by said safety m et upon the energization lof both of its cgrsl.

8. In an elevator, the combination with a car and its motor, of motor-controllingm'eans comprising reversing switches and electromagnets for'o rating same, 'a safety `m et with its co` s wound cumulatively an respectively in series with the aforesaid electromagnets, and means controlled by said safety magnet for bringing the car to a gradual sto u )on enei'gization yof both the coils of saidpsafety magnet.

9. In arielevator, the combinationwith a 4car and its motor, of reversing switches for said motor, electromagnets for operating said reversing switches, a safet magnet having coils cumulatively woun and respectively in series with-the aforesaid electromagnets, a potential switch forthernain line circuit, means for automatically reducing the speed of the car before stopping and varyi such reduction of speed in accordance wi the load, and means operated b said safey magnet upon current passing t ugh bo the first-named magnets and the coils of said safety magnet for interrupting the circuit to said potential switch to causethe same to close the circuit ofsaid automatic slowingdown means.

10. The combination with a motor, of an electro-magnet in shunt thereto, an extra field circuit., and means controlled by said electro-magnet for introducing said extra field circuit to retard the speed of the motor upon the same exceeding a predeterminedlimit.

11. The combination with a motor, of an electromagnet in shunt thereto, an electro- .magnetic potential switch, and means controlled by the aforesaid electromagnet for effecting the opening of said switch to' interrupt the circuit to the motor upon the same attainin an excessive speed.

12. T e combination with a motor, of an clectrornagnet in circuit therewith, an electro-magnetic (potential switch for controlling the motor, an tromagnet for interrupting the circuit to said rnotor-r-.ontrolling-means upon the motor attaining excessive speed.

13. The combination with a motor, of an electromagnet in circuit therewith, reversing switches for said motor, and means controlled b v said electromagnet for interrupting the circuit to said reversing switches upon the vmotor attaining excessive s eed.

14. The combination wit i a motor, of an electromagnet in circuit therewith, reversing switches for thc motor, and means controlled means controlled by said elecby said electromagnet for temporarily interrupting the circuit of an operated reversing mined s ed.

switch upon the motor exceeding a predetere combination with a motor, of an electrom riet in circuit therewith, reversing switches or the motor, electromagnetsfor operating said reversing switches, and means controlled by said electromagnet for interrupting the circuit to said second-named electromagnets upon the motor-speed exceeding a predetermined value.

16. The combination with a motor, of starting resistance therefor, a magnet in circuit with the motor, an accelerating magnet all but a portion of said RUDOLPH C. Sur'rir, Wir. H. Bmx.

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