US1215437A

US1215437A - Electric-cicuit controller.

Info

Publication number: US1215437A
Application number: US70005512A
Authority: US
Inventors: Theodore Varney
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1912-05-27
Filing date: 1912-05-27
Publication date: 1917-02-13
Anticipated expiration: 1934-02-13

Description

T. VARNEY.

ELECTRIC CIRCUIT CONTROLLER;

APPLICATION FILED MAY 27. I912.

Patented Feb. 13,1917.

ATTORNEY 2 SHEETS-SHEET I.

T. VARNEY.

ELECTRIC CIRCUIT CONTROLLER, APPLICAHON FILED MAY 2?. 1912.

Patented Feb, 13 1911 2 SHEETS-SHEET 2.

ATTORNEY WITNESSES:

said class.

STATES PATENT ()FFICE.

.FHEODORE VABNEY, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR '10 WESTINGHOUSE ELECTRIC AND MANUFACTURING- (JOMPANY, A CDRPORATION OF PENNSYLVANIA.

ELECTRIC'GIRCUIT GON'IRULLER.

Application filed May 27, 1912.

electric circuits and it has special reference to such controllers as are adapted to govern polyphase alternating current motors.

One object of my invention is to provide a controller of the class above indicated that shall have a relatively simple and durable means for automatically returning the controller to its ott' position upon the tailure of volta e in one or more of the liases of the alternating current source of energy troiii which the controlled motor is supplied.

A. second object of my invention, is to provide a particularly simple and durable con tact structure for controllers ot' the a tore- Various novel features will be hereinafter pointed out.

Figure 1 of the accompanying drawings is an elevation of a controller constructed in accordance with my invention, the inclosing tank or casing being broken away to disclose the operating mechanism and the switch contacts. v

Figs. 2 and 3 are detail views of the controller operating mechanism, and Fig. -l is a diagrammatic view illustrating the circuit connections of a motor control system our bodying the controller of the other figures.

Referring to Figs. 1, :2 and 3 of the drawings, the controller here shown comprises a stationary frame 1 which 'fOl'illS a part of an inclosing casing a cover 62, a lliiiii-containing tank or box 3, which is removably secured to the frame, a plurality of sets of stationary and movable contactmembers l, 5, 6 and 7 (liereinaiter referred to as can tacts), an operating mechanism and a release magnet 8.

The stationary contacts 4 and 5 are mounted in parallel rows on an insulating plate or slab 9, to which they are secured by bolts 10.

The plate or slab 5) is supported in a substaiitially horizontal plane by a pair of yoltes or brackets 'll', which are bolted to Specification of Letters Patent.

Patented Feb. i3, 1917.

Serial No. 700,055.

lugs 12 of the stationary frame 1 and ex tend down ardly into the fluid-containing tank The brackets 11 are mounted in substantially parallel planes and support a shaft 13 which is iiotatively mounted in a horizontal plane near the center of the tank or box 3.

-A pair of castings 1% are secured to the shaft 13 between, and adjacent to, the re-' spective bearing brackets.

An insulating strip or block 15, which is substantially parallel to the shaft 3, is secured to the castings 1% by bolts 16.

A link 18, which constitutes a portion of the operating mechanism, is connected to a projection ll of one of the castings let.

A plurality of coiitact-bearing members 19 are mounted on the insulating block 15 between the castings 14, and have perforated extensions 20 to which the contacts 6 and 7 are respectively pivoted.

Each of the contacts ti and 7 is preferably provided with a reniovable contact tip which cooperates with the corresponding portion of one of the stationary contacts 4:

and o.

Each of the movable contacts is further provided with a dmvnwardly extending bifurcated projection 21, and, a spring 22 is interposed between the project-ions of each pair of opposite movable contacts. Each of the springs 22 is supported by a telescop-.

ing guideQtl having forked ends which engage pins 24; in the bifurcated projec tioiis 21.

The contact-bear ng members 19 and the contacts thcii'iselves are provided with c0- operating stop projections 25, which are tionary rod '28 which is mounted in the frame 1 and is parallel to the shaft 26 and I a centering spring 29, which is coiled about the shaft 26 between a pair of

pawls

30 and 31.. 1

A pawl engages a notch 3st in a cam 35 which is pivotally supported on the star- Elli till

tionary frame 1 and prevents the movement of the operating handle 2'? in one direction out of the oil position of the controller.

Abell crank lever 32 is secured to the shaft 26, and the link 18 is pivotally con nected to one of its arms. Its opposite arm constitutes a latching pawl and. is pro vidcd. with notch 37 at its outer end which is adapted to engage one end of a hell crank lever 38. The bell cank lever 38 is pivoted. on a stationary pin 39 and its opposite end is connected to a movable core member so of the release magnet 8.

In addition to the movable core member 2-0, the release magnet comprises a coil 41 and stationary core; member 452 through which a guide rod d3 of the movable member extends.

The movable core member acts vertically and a releasing" pin 4% is mounted directly above it in the cover The pin 44% l as an extension 45 that projects through a hole -l6 in the cover 2 and is adapted to engage the iupper end of the rod 1-3 when pressed downwardly in opposition to a spring ll.

'lhebody of the pin 44 slides in a recess 48 in a boss 49 of the cover 2. The spring 47 surrounds the extension 45 and is interposed between the body 4+1 and the bottom of the recess 48.

A pair of relay switches 50 and 51 and coils and 53 of an auto-transhn'mer are siipported within. the frame 1 near the inag net 3.

The tank or box 3 is preferably filled with oil or some other suitable insulating liquid which tends to quench the elect ic arcs pro duced when the cooperating contact 1nemhers are separated.

The circuit coi'lnections for the system and the arrangement of the control contacts are illustrated in Fig. 4. to which reference may now he had.

he here shown, the group or l, of stationary contact members comprises contacts a, Z 0, and (Z, and the group 6 comprises cooperating contacts c, f, g and Z. 'llhe group 5 comprises stationary contacts e', 5 70, Z, we and a, and the group '7 comprises cooperating movable contacts 0, 77, and r.

The controller is adapted to govern the circuits of a three-phase electric motor which is supplied with energy from a groin crater 35 or from some other suitable source.

The operation of the controller and the circuit connections for the system are as follows:

Assuming that the controller occu 'iies its oil position, shown in Fig. l. all all th nioral'ile contacts are separated from cooperating stationary contacts and the pawl 33 so engages the notch I'll as to prevent n'icvenient of the lever 27 in a clockwise di-- rection. if the lever is moved in a counterthe circuit conductor :37.

clockwise direction, the block 15 and the mo *able contacts are given a rotary movement about the shaft 13 as an axis and the movable contacts 7 are forced into engage ment with the stationary contacts This is the starting position of the controller and the operator should. hold the lever in this position until the motor has attained a. material speed. If the lever is released, the contacts will return to the position shown in l l and the pawl 33 will fall back into the notch Ell. if, lunvever, the attendant throws the lever speedily in a clockwise direction iroin the starting position, through the oil position, to the running position, the pawl engages the surface oi the cam 85 and passes the notch 3 3: before the cam an opportunity to resume the posi tion shown in Figll.

i hen the inotor-opcrating,- position is at tained, the end oi? the bell crank lever 35 engages the notch 37 in the pawl 30 by reason of the completion of an electric circuit through the coil ll ol' the release magnet R. The controller is accordingly held in the motorcperating position as long as the coil 4. 1 continues to lie energized or until the pawl is manually rehmsed.

lfn the motor-startingr position oi" thecom troller, the transformer coil is connected across a pair lino conductors it; and 57, the contact. m and n being bridged by the contacts 1''. The transformer coil .73 is similarly connected across the line conductors 58 and 57, the contacts and y being bridged by the contact 0. tin interniwliate tap 59 of the transformer coil is conncted. through contacts Z and (j, to one terminal (30 of the motor i l tap 61 of the trans former coil is similarly cminectcd through contacts Z" and p, to a motor terminal. A third terminal as of the motor is connected, through contacts r and n, to the line conductor 57.

llclatiyely low-rolta gc energy is accordingly impressed on the motor windings in the starting position of the controller.

ll icn'lthe controller occupies its motorrunniug position, the motor terminals and as are respectively connected, tl'irouph fjtlw coils of the relay switches 51. and 50, to the circuit conductors 5t; and 58, and the motor terminal 53 is connected directly to As long: as the switches 50 and 5 are closed, the coil of the ,u'airiiiet 8 is connected across the circuit con.-

the magnet 8 .ner, ifexcessive current traverses either phase of the motor winding, one of the

switches

50 and 51 will open, the coil 8 will be deenergized and the controller will be permitted to return to its off position.

\Vhile I have shown my invention as applied to a three-phase motor, it is, of course, not limited in this respect and the circuit connections and the contact men' bers may be readily arranged to govern a motor. v

Variations in structural details may also be effected within the spirit and scope of my invention.

I claim as my invention:

1. A controller for electric circuits comprising two sets of stationary contact terminals, an intermediate rock-shaft, a contact-supporting member rotatively mounted upon the rock-shaft, two imlependently pivoted sets of contact terminals carried by said supporting member, means for resiliently connecting oppositely disposed pairs of said terminals and means for producing such rotative movements of the contact-supporting member as to effect engagement of the one or the other of its sets of contact terminals with the corresponding stationary contact terminals.

2. A controller for electric motors comprising two sets of stationary contacts, an intermediate rock shaft, a set of movable contacts rotatively supported by the rock shaft, a lever for producing such a rotative adjustment of the rock shaft as to bring the movable contacts into engagement with one set of stationary contacts for motor-starting and into engagement with the other set of two-phase contacts for motor running and means dependent upon the engagement of the contacts in the motor-running position for locking the lever to maintain said position.

3. A controller for electric circuits comprising two sets of stationary contacts, an intermediate rock shaft, a set of movable contact-Waring members rotatively supported by the rock shaft, contacts pivotally secured to the contact-bearing member at opposite sides of the rock shaft, stops for limiting the rotative movement of the movable contacts on their pivots, and springs interposed between pairs of movable contacts and tending to force them against said stops. v

4. A controller for electric circuits comprising two sets of stationary contacts, an intermediate rock shaft, a set of movable contact-bearing ported by the rock shaft, contacts pivotally secured to the movable eontzuzt-bearing mom hers at opposite sides of the rock shaft, stops for limiting the rotative adjustment of the movable contacts on their pivots, springs interposed between pairs of opposite movable contacts and tending to force them against said stops, and means for producing such rotative movement of the rock shaft as to bring the movable contacts into en-,

gagement with either the one or the other set of stationary contacts.

In testimony whereof, I have hereunto subscribed my name this ,Zith day of. May, 1912.

THEODORE VARNEY.

Witnesses:

It. \V. Cornmr n, B. B. Hmns. 4

members rotatively sup-