US767691A

US767691A - Motor control.

Info

Publication number: US767691A
Application number: US10607202A
Authority: US
Inventors: John D Ihlder
Original assignee: Otis Elevator Co
Current assignee: Otis Elevator Co
Priority date: 1902-05-05
Filing date: 1902-05-05
Publication date: 1904-08-16
Anticipated expiration: 1921-08-16

Description

PATENTED AUG. 16, 1904.

J. 1). IHLDBR. MOTOR CONTROL.

APPLICATION FILED MAY 5, 1902.

N0 MODEL.

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UNITED STATES PATENT OEEicE.

JOHN D. IHLDER, OF YONKERS, NEIV YORK, ASSIGNOR TO OTIS ELEVA- TOR COMPANY, OF EAST ORANGE, NEIV JERSEY, A CORPORATION OF NEW JERSEY.

MOTOR CONTROL.

SPECIFICATION forming part of Letters Patent No. 767,691, dated August 16, 1904,-

Application filed May 5, 1902. Serial No. 106,072. (No model.)

To all 1071,0717, it may concern:

Be it known that I, J oHN D. IHLDER, a citizen of the United States, residing at Yonkers, in the county of lVestchester and State of New York, have invented certain new and useful Improvements in Motor Control, of which the following is a specification.

My invention relates to motor control; and its objects are primarily to enable an electric motor to be automatically controlled in a simple and convenient manner which reduces the liability of injury to the motor and prevents the starting-current from rising beyond a predetermined amount.

Further objects of my invention will hereinafter appear; and to these ends my invention consists in the system of motor control devised for carrying out the above objects and having the general mode of operation substantially as fully described and shown in the accompanying specification and drawings, in

which Figure l is a diagrammatic view showing circuits and apparatus embodying one form 2 5 of my invention, and Fig. 2 is a diagrammatic view showing a modified form of my invention.

Referring to the drawings, A represents a motor, which may be of any suitable type, but

shown in this instance as a shunt-wound motor adapted to be connected in circuit with the supply-mains (indicated by and and provided with a series field-winding B and a shunt-field C, the shunt-field being connected 3 5 to the mains at the points a and 6. A suit able switch D is arranged to control the admission of current to the motor-armature, and the throwing of the switch-lever 0 into contact with contacts (Z and 6 will first complete the circuit of the electromagnet E, connected across the mains and controlling contacts f in the main armature-circuit. The energizing of magnet E closes contacts f and completes the circuit to the motor through resistances F and G and the series field-winding B, which also includes, preferably, a portion of the starting resistance H for purposes of regulating. The completion of the armature-circuit throws the full -line potential on magnet 1, shown connected across the line from a point to the switch D, causing magnet I to actuate its core 1: and close circuit between contacts 1 and 5 and the insulated contact 6 and 7 on the core, thereby short-circuiting a portion of resistance F and completing a circuit through the shunt-winding /t of the doubly-wound magnet 1. The doubly-

wound magnets

1, 2, and 3 are assumed to be diiierentially wound, being provided with shunt-windings it, connected in parallel to each other and in shunt to the main line, and also provided with windings 'in series with the line, the series windings being of insuflicient strength,however, to move acore Z; even with maximum current. After magnet I has closed its contacts and short-circuited a portion of resistance F the current will have increased sufficiently to start the motor under all loads, and although but one magnet I is illustrated for the sake of simplicity in the diagram of Fig. 1 any desired number of magnets I may be used to short-circuit the resistance F in a series of steps to admit the maximum permissible strength of starting-current. The starting of the motor cuts down the armature-current and the strength of the series winding j of magnet 1, while the shunt-winding lb of said magnet gradually comes up to maximum strength due to the diflerence of potential between the points Z and a on the line between which the shunt-winding is connected, this difference of potential not being quite the fullline potential, since the point Z is taken between the resistance F and the motor, which is the preferable arrangement, because the fall of potential through the resistance F aids in regulating the magnet 1, the fall of potential being greater with the maximum current which causes the closing of the contacts of magnet 1 than with a reduced current. As the current decreases and as the resistance F decreases with a plurality of such starting-magnets I or with the one magnet shown the shunt-coil ii of magnet 1 becomes strengthened, while the series coil jbecomes weakened until a point is reached where the core I: is actuated to close circuit between contacts 8 and 9 and insulated contacts 10 andll on the core, thereby short-- circuiting more of the starting resistance F and completing the circuit of the shunt-coil h of magnet 2. The short-circuiting of resistance F again increases-the current to a maximum, from which it is reduced by the further increase of armature speed, thus repeating the operation for

magnets

2 and 3 as described for magnet 1, until finally circuit is closed between contacts 12 13 and 14 15 of magnet 2 and contacts 16 17 and 18 19 of magnet 3, whereby all of the resistance and the series field-winding B are short-circuited.

It will be seen that as the

magnets

1, 2, and 3 operate the series windings 'j are short-circuited in turn, and when magnet 3 operates to close contacts 16 and 18 a circuit is completed to a third winding on magnet 3 and to a magnet g, the circuit of magnets 19 and 9 being connected, as shown in this instance, across the line. Coil 2 operates as a holdingcoil to maintain contacts 16 17 and 18 19 closed, and magnet q actuates contacts 20 to break the circuit of all the shunt-windings It, so that they do not consume current after the motor has started.

According to my invention the current cannot rise beyond a predetermined amount, for any increase of current beyond the predetermined amount in starting so strengthens a series winding j that the operation of cutting out resistance does not continue until the current has again reduced to the desired amount. In other words, my apparatus is so constructed that the amount of starting-current which can be admitted is limited, for when the startingcurrent rises beyond a predetermined amount the operation of cutting out resistance will be suspended.

To stop the motor, the lever c is moved to break circuit with contacts (Z and 6, contact d being longer than 6, so that circuit is broken with contact 0 first. thus breaking the circuit of magnet q first and throwing the resistance back into circuit before magnet E is denergized to break the armature-circuit.

It is not necessary that each shunt-winding 72, should have its circuit separately controlled, as described in connection with Fig. 1, nor that there should be a magnet I or magnets provided for the preliminary operation of admitting. the maximum starting-current, for the maximum starting-current may be admitted at once on the first step, if desired, as provided for in Fig. 2.

In Fig. 2 the shunt magnet-windings it of

magnets

1, 2, and 3 are shown in series with each other and connected to the line in such manner that circuit through them is always completed when switch D is closed. The series windings 'of these magnets are arranged in the same manner as before, and this whole construction requires a more exact adjustment than that shown in Fig. 1 to obtain the same operation. The shunt and series windings on --may be wound to different strengths with the

armatures

21, 22, and 23 arranged at the same distances from the cores k. In this latter case the shunt-windings it may decrease in strength from magnets 1 to 3, or else the series windings j may increase in strength from magnets 1 to 3, as may be desired, so that magnet 1 always operates to attract its armature on less magnet strength than magnet 2 and magnet2 operates on less magnet strength than magnet 3, the whole operation of the apparatus shown in Fig. 2 being substantially the same as that shown in Fig. 1.

Without limiting myself to the construction shown and described, I'claim 1. The combination with a motor having an armature, of a controlling means therefor dcpendent for its operation upon the differential action of the potential and current of the motor-armature, substantially as set forth.

2. The combination with a motor having an armature, of a step-by-step controlling means comprising an actuating mechanism for each step dependent for its action upon the potential and current of the motor-armature, substantially as set forth.

3. The combination with a motor having an armature, of a step-by-step controlling means comprising an actuating mechanism for each step dependentfor its action upon the differential action of the potential and current of the motor-armature,substantially as set forth.

4. The combination of supply-mains, a motor-armature, a potential-reducing device,and regulating means for said device connected in series between said mains and other regulating means cooperating with the said aforesaid regulating means, connected in a circuit in parallel with said armature and in series with said device, substantially as set forth.

5. The combination of supply-mains, amotor-armature, a potential-reducing device,and regulating means for said device connected in series between said mains and other regulating means cooperating differentially with the aforesaid regulating means, connected in a circuit in parallel with said armature and in series with said device, substantially as set forth.

6. The combination of supply-mains, a motor armature, a resistance, and regulating means for said resistance connected in series between said mains and other regulating means cooperating with the aforesaid regulating means, connected in a circuit in parallel with said armature and in series with said resistance, substantially as set forth.

7. The combination of supply-mains, a motor-armature, a resistance, a regulating means for said resistance connected in series between said mains and other regulating means cooperating differentially with the aforesaid regulating means, connected in a circuit in parallel with said armature and in series with said resistance, substantially as set forth.v

8. The combination with a motor having an armature, of a controlling means for said motor comprising an actuating-clectromagnet, said electromagnet having a winding depending for its energy upon the potential of the motor-armature and another Winding dependent for its energy upon the current of said armature, substantially as set forth.

9. The combinationwith a motor having an armature, of a controlling means for said motor comprising an actuating-electromagnet, said electromagnet having differential Windings, one of which depends for its energy upon the potential of the motor-armature and another of which is dependent for its energy upon the current of said armature, substantially as set forth.

10. The combination with a motor having an armature, of a step-by-step controller therefor, an electromagnet for each step, each of said electromagnets having differentiallywound coils, of which one depends for its energy upon the current and the other upon the potential of said armature, substantially as set forth.

11. The combination with a motor having an armature, of a resistance, supply-mains and a controller for cutting out said resistance step by step comprising aseries of electromagnets, each of which has differentially-wound coils, one of which is connected in series with said armature and resistance between said mains,

the other being connected in a circuit in parallel with said armature and in series with the armature-resistance, substantially as set forth.

12. The combination with a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step dependent for its operation upon the potential and current of the motor-armature and upon a mechanism of a preceding step, substantially as set forth.

13. The combination with a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step dependent for its operation upon the differential action of the potential and current of the motor-armature and upon a mechanism of a preceding step, substantially as set forth.

14. The combination with a motor having an armature, of a step-by-step controlling means comprising an electromagnet for each step having windings, one of which windings depends for its energy upon the current of the motor-armature, the other of which windings is dependent for its energy upon the potential of said armature, the circuits of said windings being controlled by an electromagnet of a preceding step, substantially as set forth.

15. The combination with a motor having an armature, of a step-by-step controlling means comprising an electromagnet for each step having differential windings, one of which windings depends for its energy upon the current of the motor-armature the other of which windings is dependent for its energy upon the potential of said armature, the cir cuits of said windings being controlled by an electromagnet of a preceding step, substantially as set forth.

16. The combination with a motor having an armature, of a step-by-step controlling means comprising a potential-reducing device, mechanism for each step, each of said mechanisms having a coil dependent for its energy upon the potential of said armature, and connections whereby the said mechanisms successively connect the coils of succeedingmechanisms to different points of said potential-reducing device, substantially as set forth.

17. The combination with a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step and a potential-reducing device, each of said mechanisms having a potential-coil dependent for its energy upon the potential of said armature and a current-coil dependent for its energy upon the current of said armature, and connections whereby the said mechanisms successively connect the potential-coils of succeeding mechanisms to different points of said potential-reducing device, substantially as set forth.

18. The combination with a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step and a potential-reducing device, each of said mechanisms having apotential-coil dependent for its energy upon the potential of said armature and a current-coil dependent for its energy upon the current of said armature, said potential and current coils being differentially wound, and connections whereby the said mechanisms successively connect the potential-coils of succeeding mechanisms to different points of said potential-reducing device, substantially as set forth.

19. The combination with a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step,

' and a resistance, each of said mechanisms having a coil dependent for its energy upon the potential of said armature and connections whereby the said mechanisms successively connect the coils of succeeding mechanisms to different points of said resistance, substantially as set forth.

2(). The combination with a motor having an armature, of a step-by-step controlling & 767. 691

means comprising a mechanism for each step and a resistance, each of said mechanisms having a potential-coil dependent for its energy upon the potential of said armature and a current-coil dependent for its energy upon the current of said armature, and connections whereby the said mechanisms successively connect the potential-coils of succeeding mechanisms to different points of said resistance, substantially as set forth.

21. The combination With a motor having an armature, of a step-by-step controlling means comprising a mechanism for each step and a resistance, each of said mechanisms having a potential-coil dependent for its energy scribing Witnesses.

JOHN D. IHLDER.

Witnesses: I

O. B. MANVILLE, P. WV. N EWELL.