US1016470A

US1016470A - Motor-controller.

Info

Publication number: US1016470A
Application number: US49942109A
Authority: US
Inventors: Thomas E Barnum
Original assignee: Cutler Hammer Manufacturing Co
Current assignee: Cutler Hammer Manufacturing Co
Priority date: 1909-06-01
Filing date: 1909-06-01
Publication date: 1912-02-06
Anticipated expiration: 1929-02-06

Description

T. E. BARNUM.

MOTOR CONTROLLER.

APPLICATION IILBD JUNE 1, 1909.

1,016,470, Patented Feb. 6, 1912.

uR-ITED sjTArEs PATENT oFFmE.

r'nomes 'BARNU or MILWAUKEE, .WISCONSIN, Assmnoy-To THE cornea- HAMMER MFG. 00., or jMILWAUKEE, wxsconsm; A CORPORATION or Wisconsin.

MoToR-coN'riwLLER.

To all ilihom it may concern: I

Be it known that I, T}1OM.\S E. 'BARNUM, a citizen of theUnited States, residing at Milwaukee, in the county of Milwaukee and 5 State of \Visconsin, have invented new and embodies my invention in one form.

useful Improvements in Motor-Controllers,

of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, form ng apart of this specification.

My invention relates to improvements in controllers for electric motors and' more particularly to" controllers for operating one or I more motors eitherat slow speed or at normal high speed. Such controllers are p'articul arly adapted for use in connection with motor-operated printing presses and various other kinds of {motor-operated machinery,

. where it is desired to'operate the driven mechanism at slow speed and then stop the same in predetermined positions for inspection, adjustment, repairs, etc. A Such an operation of a printing press is-commonly known as teasing, inchingor jogging the p es -,.i One object of my invention is to provide means whereby the motor may be operated at different predetermined slow speeds. I A further object of my invention is 'to provide auxiliary means for starting 'the motor for teasing or inching when the friotion of rest of the driven mechanism is so great that the motor will not starti imder the control (2 the usual teasing or inching means:

Astill further objcct of my invention is to provide one or more switches arranged at suitable points around the driven mechanism, anyone of whichmay be operated to control both the usual teasing means and the auxiliary teasing means. n v

Various other objects and advantages of my invention will be hereinafter clearly and fully set forth. I

For the purpose of more fully disclosing thenature of my invention, 1 shall describe the system of control diagrammatically illustrated in the accompanying drawing which It should be understood, however, that my invention is not limited to the particular systemfof t'zontrol illustrated in the drawing. but capable of various modifications.

The system of control illustmted includes Specification of Letters Patent.

Patented Feb. 6, 1912.

Applicationdlled June 1, 1909. Serial No. 499,421.

i a nanu'ally operated controller 1, a main switch 2, an auxiliary speed controlling switch an auxlliary teasing switch 4, and

a dynamic brakingswitch 5.

As will be hereinafter set forth, the main switch 2 is arranged to complete the circuit of the motor 6. The motor which I have shown for the purpose of illustration is of the compound type, being provided with an armature A, a series field windingF and a shunt field winding f. It should be understood, howeveigthat my invention is applicable to other thancompound motors 'Ifhe speed of the motor is controlled by the controller 1 which I shall now describe.

This controller comprises a movable element 7 which carries three contact brushes 8, 9 and 10. As the member 7 isy-moved to leaving. this segment, to engage a segment 16, In initial position of the member 7, the brush 8 engages a deadcontact 17. .The series of contacts 11 are connected to anarmature resistance 18, while the series of contacts 14 are connected to a field regulat ing resistance 19 In addition to the'brushes mentioned. the member 7 carricstwo electrically connected brushes 20 and 21, ar-

ranged to engage contact segments22 and 23 respectively. while the member 7 is within a predetermined distance from initial positicn. Vllhile the brushes 20 and} 21 are,

electrically connected, they are both insulated from the member 7 and are provided merely to electrically connect the contact segments 22 and 23 when the member 7 is in certain positions for the purpose l'ierein'after set forth.

The switches 2, 3, 4 and 5 are provided with operating windings 223i, 4 and 5* respectively. For controlling the circuits of the operating windings of the switches 2 and 4, I provide suitable master switches 24 which may be of any preferred type and of any desired number.

ments 25. 26, 27 and 28, each adapted to engage a s'tatlonarycontactfinger; Iii-prac- As illustrated, the switches 24 are provided with'contact seg--.

tice, T preter'to provide the switches 24: with suitable-centering springs 29 for normally holding the, same in the position illustrated; that is, in such a position thatthe segments 25 and 26 normally engage theirrespective contact fingers, it, of course, being understoodthat the switchesmay be moved soas to disengage the segments 25 and 26 from their stationary contacts. In practice, i also preferably provide an overload swltch 30, having an operating winding 31. The function of this switch will be hereinafter set forth.

, The circuit connections of the system will be clearly set forth in the following descrip tion of t e operation of the controller.

' vAssuming the several switches to be in i the position illustrated in the drawing, no

engage its stationary contact. This comlower master switch as 2 1.

current would flow through the system from the main lines 32' and 33. In order to start the motor either for teasing or for running,

it is first necessary to move the controller arm 7 so that the brush 8 carrle'd thereby will leave the dead contact 17 and engage the contact segment 15. -When.'the member pletes a circuit from main line 32 through one side of the double pole switch 34., by conductor 35 to member 7 of the controller 1,

thence through said member by brush 8 to segment 15, by

conductors

36 and 37, through the winding 2 of the main switch 2, by conductor 38 to segment 27 of switch 24 to segment 26 thereof and by conductor 39 through the overload switch 30 to the opposite side of the main line. This causes the energization of the winding 2 which thereupon closes the switch 2. Closure of the switch 2 completes the motor circuit from the movable member of the controller 1 by brush 10 to one of the contacts 11., thence through the armature resistance 18 to segment 12, by conductor 40 through the motor armature A. and series field winding F, and through main switch 2 to the opposite side of the main line. At the same time, circuit is also closed from brush 9 of the rheostat member 7 by contact segment 13 to conductor 41 through the shunt field winding 7 of the motor. The motor is thus started with all of the armature resistance in circuit. To increase the speed of the motor, the controlling member 7 should be moved to the right to gradually remove the armature resistance from circuit. To still further increase the speed of the motor,

after all ofthe armature resistance has been scream removed from circuit movement of the controlling member 7 may be continued so that the brush 9 thereof will pass over the contacts 14, thereby inserting the resistance 19 in the "shunt field circuit of the motor. When the motor has attained desired speed, the member 7 may lee-stopped and left without further attention.

Upon the brush 8; of the member 7 leaving the segment 15 and passing onto the seg ment 16, a resistance 42 is inserteohin circuit with the winding of the main switch 2.

The insertion of this resistance prevents the reclosure-- of the main switch 2., should itopen. until the movable member 7 of the controller is movedjback onto the contact segment 15, thereby short-circuiting the resistance 42. The purpose of thisarrangement is to prevent starting of the motor until the member 7 has been returned to its initial position to remove all of the resistance from the shunt field circuit of the motor and to insert a predetermined amount ofthe resistance 18in the armature circuit.

Immediately upon closure of the main switch, the master switch 24. or 24, whichever was operated, may be released, thereby causing the segment 27 to disengage its Sta-- tionary contact. This would interrupt the circuit of the winding 2". but for the factthat a maintaining circuit established therefor from conductor 38 by conductor 43. through a resistance 44 to segment 25 of the master switch 24. thence to segment 26 thereof. by conductor 45, to segment 25 of the master switch 24*. to segment 26 thereof. and thence to the negative side of the line as already traced. The resistance 44 is provided. in this maintaining circuit. to prevent closure of the switch 2 by merely movinsrthe member 7 into engagement with the segment 15. This arrangement necessitates closure of the motor circuit by means oi one of the master switches. and thus renders it impossible for the attendant to start and ston the motor by means oi the controller 1 as they would be likely to do if no such pro-- vision was made. Such an operation of the member 7 would be injurious to the controller 1.

Having thus described how the motor may be started and-brought up to normal speed. I shall now describe the teasing op eration.

In order to tease or inch the driven mechanism, it is first necessary to close the main switch 2. As has previously been' set forth, in order to close the circuit of the operating winding of this switch, it is first necessary to move the controlling member 7 into engagement with the contact segment 15. The main switch 2 may then be closed in the manner previously set forth by operating either one of the switches 2 or 24. The

speed 6. whi h a. motor may be inched or ios As previously set forth, the insertion of the resistance 42 prevents reclosure of the main switch 2 after it has once been opened, and thus the motor could not be teased if the controllingmember 7 was moved into engagement with contact segment 16.

If it is desired to tease the motor at a still lower speed than is provided by the controller 1, the member 7 should be left in such a position that the brushes 20 and 21, carried thereby, will electrically connect the segments 22 and 23. The bridglng of the segments 22 and 23 connects the operating winding 3" of the switch 3 across the terminals of the motor armature A. This circuit may be traced from one terminal of the motor armature by conductor 40 to contact segment 12, by conductor 50 through the segments 22 and 23 by conductor 51, through the winding 3, by conductor 52 to the opposite terminal thereof. Hence, when the motor starts, it generates a radually increasing C. E. M. F. When the motor attains a predetermined slow's'peed, theC. E. M. F. generated thereby, is sufiicient to cause the winding 3' to respond to close the switch ,3. Closure of the switch 3 completes a circuit in parallel to the motor armature, which circuit maybe traced from conductor 40 through a variable resistance 53, through switch 3, by conductor 52 to the series field winding F. The establishment of this parallel circuit reduces the flow of current through the motor armature in a well known manner, and. consequently, decreases the speed thereof. The maximum speed at which a motor may thus operate with the controlling member 7 in the position described may be regulated by inserting more or less of the variable resistance 53 in the shunt circuit around the motor armature. \Vhilethe controlling arm'7 engages contact segment 15, the motor may be started and stopped any number of times by .merely operating anyone of the master switches.

It frequently occurs that the friction of rest of the driven mechanism is so great that the motor will not start upon closure of the main switch 2, and, for starting the motor under such conditions, I have provided the switch 4. The circuit of the operating engage its stationary contact.

to the win ing of the main switch.

winding of this switch may be closed at any time while the controlling member 7 e11- gages the contact segment 15 by moving either of the master switches into such a position that the segment 28 thereof will This connects the o crating Winding 4 in parallel This circuit may be traced from conductor 36, by conductor 54, through the winding 4, by conductor 55 to the switch'contact'28 of either master switch, thence to contact 26 thereof, and thence back to the negative side of the main line as already traced in connection with the-winding 2. Upon closureof theswitch 4, the motor circuit extends from main line 32 through the switch 4, by conductor 56, through only a portion of the resistance 18 and through the motor already traced. It will thus be seen that closure of the switch 4 short-circuits a considerable portion of the resistance 18. and, consequently, provides for a greaterstarting current for the motor than can be obtained through the manipulationof the controlling arm 7. Ordinarily, as soon as the motor has started, even though the friction of rest is great, it will operate thereafter with a less supply of current. -Thus, when the motor has been started, the master switch may be released, thereby deenergizing the switch 4, but maintaining the switch 2 in closed positionas already set forth.

Then the motor circuit has been closed for jogging or teasing, or, in fact, whenever the motor is in operation, it may be stopped by manipulating any one of 'the master switches. To stop a motor, one of the master contacts, thereby opening the maintaining circuit of the winding 2*.

The main switch 2* is arranged to operate an auxiliary switch 57, which is adapted to be closed when the main switch 2 is opened. Closure of the switch 57 completes a circuit from one terminal of the motor armature by conductor 40, through switch 57, by conductor 58, through the winding 5*"01 the dynamic braking switch I, by conductors 55) and 52 to the opposite side of the .motor armature. Hence, if the motor continues to operate under the impetus of its load after the switch 2 is opened, it will act as a generator and send a current through the circuit of the winding 5*. This causes the closure of the switch 5 which then completes a dynamic braking circuit across the terminals of the motor. This circuit may be traced from one terminal of the motor armature by

conductors

52 and 59, "through switch 5, by conductor 60, through a portion of the resistance 18, by contact segment 12, to conductor 40 and thence to the opposite terminal of the motor armature. The establishment of this circuit quicklyv hrings the motor to rest. When the motor is hrought to rest, the winding 5 becomes denergized, thereby causing the switch 5 to open. e The purpose of the overload switch 31 is to open the circuit of the operating winding of the main switch 2 upon an excessive flow of current through the motor,-thereloy causing the opening of said main switch. The motor cannot be again started until a suiticient amount of protecting resistance 'is inserted-in circuit therewith,"

' What I claim is:

l. In a controller for electric motors in combination, a plurality of devices for starting the motor under difierent potential con-.

ditions, and common controlling means for said devices.

2. lln a controller for electric motors, in-

combination, a plurality of devices for starting the motor under difierent potentlal conditions, and one or more controlling devices,

each adapted to control the operation of all of said starting devices.

motor at a relatively slow speed in combination, a resistance, a. switch for closing the motor circult wlth said resistance included therein and a second switch adapted to be operated to remove a portion of said resistance to start the motor upon fallure of said first mentioned switch to start the motor, said second mentioned switch being antomatically caused to reinsert said portion of said resistance.

4. in a controller tor operating an electric motor at a relatively slow speed in combination, a switch for closing the motor circuit, a variable resistance, a controlling element adapted to be set to include a predetermined amount of said resistance in the motor circuit upon closure of said first mentioned switch, and a second switch adapted to be operated to temporarily remove a portion of said resistance to start the motor upon failure of said first mentioned switch to start the motor.

5. in a controller for operating an electric motor at a relatively slow speed in combination, a resistance, a switch for closing the motor circuit with said resistancc'included therein, a second switch for removing a portion of said resistance to start the motor upon failure of said first mentioned switch to start the motor, and a controlling device for causing operation of one or both of said switches at will, said controlling device 'icnding to cause said .second' mentioned switch to reinscrt said portion of said resistance.

6. in a controller for electric motors, in combination, a resistance,- a controlling element therefor included in the motor circuit,

- an electromagnetically operated switch for controlling the motor circuit, means necessl- 3. in a controller for operating an electric.

noiaero tating the movement of said element to incessitating movement of said'element to in-' clude at least a predetermined amount of said resistance in the motor circuit prior to the operation of said switch, an electromagnetically operated switch adapted to be actuated to remove a portion of said resistance from the motor circuit, and one or more master switches each adapted to control the operation of both of said switches.

8. in a controller for electric motors, incombination, a resistance, an electroresponsive switch for closing the motor circuit with a predetermined amount of said resistance included therein, an electroresponsive switch adapted to be actuated to remove a portion of said resistance from the motor. circuit, and one or more master switches, each adapted to be actuated .to cause-one or both of said switches to respond, said master switches, when returned to normal position, being adapted to cause said second mentioned switch to open and to maintain said first mentioned switch closed.

9. in a controller for electric motors, in combination, a resistance adapted to be included in the motor circuit, a movable controllingelement therefor, an electroresponsive main switch for controlling the continuity of the motor circuit, means necessitating movement of said element to include at least a predetermined amount of resistance in the motor circuit prior to the operation ofsaidmain switch, an auxiliary electroresponsive switch adapted to be oper ated to remove-a ortion of said resistance from the motor clrcuit, means for controlling the operation of both of said switches, and means for automatically establishing a dynamic braking circuit for the motor upon ice from the motor circuit and one or more master switches, each adapted tocause one ,or both of said switches to respond.

adapted to automatically operate when said element is in a predetermined position to maintain the speed of the motor within pre determined limits.

13. In a controller for electric motors, in combination, a potential regulating device for the motor having a movable element, an electroresponsive main switch, means necessitating movement of said element to a position within predetermined limits prior to pressed upon the motor, and means for controlling the operation of said auxiliary switch, said means when returned to normal position being adapted to cause said auxiliary switch to return to initial position.

12. In a controller for electric motors, in combination, a potential regulating. device for the motor having a movable element, an electroresponsive main switch, means necessitating movement of said element to a position Within predetermined limits 'prior to the closure of said main switch, an auxiliary electroresponsive switch adapted to be operated. to increase the potential impressed upon the terminals of the motor, and means the closure of said main switch, an auxiliary clectroresponsive switch adapted to be oper ated to increase the potential impressed upon the terminals of the motor, an electromagnetically operated switch arranged to have its operating winding connected across the terminals of the motor armature when said element is within predetermined limits,

' and a resistance arranged to be connected in parallel to the'motor armature by 'said last mentioned switch to maintainthe speed of the motor within predetermined limits.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

' THOMAS E. BARNUM.

Witnesses:

FRANK H. HUBBARD, WALTER E. SARGENT.