US931126A - Control switch and system. - Google Patents

Description

H; D. JAMES. I CONTROL SWITCH AND SYSTEM.

' APPLICATION FILED DBO. 14,1908.

931,126. Patented Aug. 17,1909.

2 SHEETS-SHEET 1.

WITNESSES:

H. D. JAMES. CONTROL SWITCH AND SYSTEM. APPLIQATION'IILED nno.14,19os-.

93 1,1 26. Patented Aug 17, 1909.

\NVENTOR wig/(0AM ATTORNEY WITNESSES:

of Pittsburg, in the county of Allegheny and -trated partially in section and partially diawhen the movable core member is raised, en-

Y project into the res 2 is provided, and it is also provided with vided with a rod UNITED STATES.

HENRY 1). JAMES, OF PITTSBURG,

PENNSYLVANIA, ASSIGNOR'TOIWESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

CONTROL swrrcn'am) srs'rnn.

Specification of Letters Eatenti :Patented Aug. 17, 1909.

Application filed December 14, 1908. gerial; R0.

To all 'whom it concern:

Be it known that I, HENRY D. -James-a citizen of the United States, and a resident State of Pennsylvania, have invented a new and useful Improvement in Control Switches and Systems, of which the following is a specification.

My invention relates to controlling switches and systems for electrical translating devices, and it has special reference to systems and switches which are utilized for so controlling electric motors that they may be started from rest and brought to operatmg speed autoi'natically and under such con- 1S provided with a stop ditions as to avoid injury to either the motor or the controlling apparatus.

My invention embodies a. plurality of switches which are so connected together and to a plurality of resistance sections that they shall operate auton'latically to cut the resistance sections successively out of the motor circuit and be automatically delayed in operation sufficiently to avoid injury by reason of excessive currents in the motor circuit.

In the accompanying drawings, Figure 1' is 'a view, partially in elevation and partially in section, of a switch constructed in accordance with my invention, and Fig. 2'is a dia v gram o't circu ts in which a plurality of switches like that shown in Fig. l are illusgrammatically.

Each of the main switches of my system is provided with an operating coil 1 which is mounted in a frame 2 and with a staalso mounted in said The movable core portion 4 is proupon the upper end of. which is mounted a eontact-terminal 6 which,

frame.

gages a stationary contact terminal 7.

Two blow-out magnet coils 8 are mounted adjacent to'and at opposite sidesof the contact terminals -6 and 7, and two core memhere or armatures"9 and 1O are supported by the frame 2, t 'e 'upper' ends of which ectlve coils 8. .The'armature or core mhmber Qmay be immovable but the armature or member 10 is pivotally mounted in lugs 11 Withwhitsh the frame an inwardly projecting arm 12 at its lower end which is bifurcated to embrace the rodi 5 and is in such by a collar 13 on terminals 6 and- .armature or member 10 being thus held in ts outermost position. One of the lugs 11 position to be engaged by a lug or projection 15 on the armature or member 10 when the latter is moved inwardly upon its pivot by reason of the pull exerted upon it by the corresponding blowout coil.

The outer side of the upper endof the armature or core member 10 is provided with a contact terminal piece 16 which engages a stationary contact terminal piece 17 when the armature or core member 10 is in its outermost position, and the said member is held in that position when the blow-out coil isdenergized, and when it is energized to less than a predetermined degree, by means of a coil-spring 18, the upper end of which is connected to a lug 19 on the armature or core member 10, and the lower end of which is connected to-a screw-threaded rod'20 which projects through a lug 21 on the frame 2 and is provided with anut 22 "for the purpose of varying the tension of the spring 18 in accordance with the requirements of the service.

Referring now to Fig. 2 of the drawings, a motor 23 is supplied with energy from a suitable source through line conductors 24 and 25 and, for-the purpose'of varying the current supplied to the motor, three resistance sections- 26, 27 and 28 are provided. For the purpose of controlling the motor 23 by cutting the resistance sections successively out of circuit, four main switches 29, 30, 31 and 32 are provided, each of switches 30, 31 and 32 being like that shown in Fig. 1, and switch 29 being of the same general character but having two stationary armatures or core members {land 9" for the blowout coils and having none of the accessory devices which are employed in connection with the movable core member 10. Each of the switches 29, 30 and 31 is provided with an auxiliary switch 33, which is closed when the main contact terminals are closed and the switch 32 is provided with a double auxiliaryswitch 34 which serves to close one auxiliary circuit when the. main switch 1s closed and another auxiliary circuit when the main switch is open. The'operation of the switches and system piece 14 which is inv i switch 33 will therefore be closed, thus cut is as follows: In order to start the motor 23, a master switch is closed, thus closing a circuit from the main line conductor 24 through the operating coil of switch 29 and the lower members of switch 34 to the lineconductor 25. The operating coil of the switch :29, being thus energized, moves the contact terminals 6 and 7 into engagement and also closes the corresponding switch 33, thereby closing the circuit of the motor through all of the blow-out coils 8 and all of the resistance sections. .The first rush of current through the blow-out coils is suificient to move the armatures or core members 10 and thus separate the contact terminals 16 from the contact terminals 17 and, therefore, the switch 30 cannot be closed until the current falls to such value that the spring 18 may bring the contact terminals 16 and 17 again into engagement. \Vhen this engagement is effected, an auxiliary circuit is established throughthe switch 33 ertaining to switch 29, the operating coil 0 switch "30 and the contact terminals 16, 17' and 7 of this switch and the main switch 30 and its ting the resistance section 26 out of the motor circuit.

The operation of switch 31 will be delayed in the manner above set forth, by reason of the fact that the rush of current when the resistance section 26 is cut out will cause the blow-out magnet of switch 30 to separate the contact terminals 16 and 17 of this switch in the manner already described, and, when the current falls to normal value, this I switch will operate in the manner just described.

The same operation will be efl'ected in'connection with switch 32 except that, when this switch operates, it will close the upper member of the auxiliary switch 3% and open the lower member, thus including a. resistance 36 in the auxiliary circuit which is maintained during the operation of the motor. As soon as any one of the main switches 30, 31 and 32 -is closed, its arm 12 will be engaged by the collar 13 on the rod 5 and the movable core member 10 will thus be prevented from oscillating back and forth, as it would do-under variations in current, rovided it was free to move.

Variations in' structural details and eircuit connections which do not effect material changes in mode' of operation or result are to be understood as within the scope of my invention.

I claim as my invention:

1. An automatic switch cuits comprising a, stationary contact terminal, a movable contact terminal, an operating coil a blow-out coil and a movable armature or core for said blow-out coil havswitch and means for holding said armature or core member in position tokeep said auxiliary switch closed While the main switch is closed.

2. In a switch for electrical circuits, the combination with stationary and movable contact terminals, of an operating coil, a blow-out coil, a spring-restrained movable armature or core member for said blow-out coil and means for holding said armature or core member in its spring-restrained position when the main switch is closed.

3. In a switch for electrical circuits, the combination with stationary and movable contact terminals, of an operating coil, a blow-out coil, a spring-restrained movable armature for said blow-out coil having one contact terminal of an auxiliary switch and an arm or projection adapted for, engagement by a portion of the movable member of the main switch, when in its circuitclosing position, to lock said armature in its spring-restrained position.

4. In a motor-controlling system, the combination with a series of resistance sections,

HENRY D. JAMES.

Witnesses: I

FRANK M. J. MUnrnY, BIBNEY HINEB.

for electrical ciring one contact terminal of an auxiliaryof a series of cooperating switches having

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