US531432A - Cueeeni motors - Google Patents

Description

(No Model.)

L; BELL. STARTING ALTERNATING- CURRENT MOTORS vN0. 531,482. Faten'ted Dec. 25,1894.

Hal.

UNITED STATES PATENT Osman,

LOUIS BELL, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE GTNERAL ELEOTRIC COMPANY, OF SAME Pl-JACE.

STARTING ALTERNATING-CU R-RENT MOTORS,

SPECIFICATION forming part of Letters Patent No. 531,432, dated llecemher .25, 1894.

Original application filed July 3, 1893, Serial No. 479,457- Dividod and this application. filed hiarch 12, 3.894, Serial No. 503,258.

(No model.)

To all whom it may concern:

Be it known that I, LOUIS BELL, a citizen of the United States, residing at Boston, in

the county of Suffolk, State of Massachusetts,

sion systems so'that the coils may be placed in series when the motor starts and afterward may be placed in multiple when the motor attains speed.

This-application is a division of my application, Serial N0. 479,457, filed July 3, 1893.

As is Well known, the starting of alternatingcurrent motors presents peculiar ditliculty by reason of the fact that not only is the ohmic resistance of the armature conductors considerable, but the high self-induction of these conductors also prevents the passage of any considerable current at starting. It is also well known that for a few moments the armature will stand a potential very much higher than that which is adapted to run it ordinarily, and this fact I take advantage of bythe arrangement of the transformer coils just referred to.

The accompanying drawings show diagrammatically illustrations of my invention, Figure 1 shows the entire system, anilFi x 2 an enlarged view of a switch which l may employ-in connection with, the transformer, Referring-by letter, G is the generator so plying alternating current to the mains o connected to the primary P of the transformer,

the secondaries; S, S of which are divided (in the case illustrated) into two parts, switch lLis illustrated herein as a throe po switch and is provided with contacts 1 to 10,

M is the motor, illustrated as of the induction type, and having shading or Bhortscire, thence thron h the or,

cuited coils s, 3, (its. as in the patents to Elihu Thomson, Nos. 063,186 428,650. Reterring now to 2, l. illustrate on enlarged scale switch to which reference has been made. starting the motorlii switch it thrown to the loft and the current passes in series the two secondaries S, S, as follows: Entering the line a it passes to contact 9;, by switch arm 6 to contact 1, thro ,gh' one of the secondary coils S to contact 6, lay the f to contact 5, through. the other secondary coil to contact 8, by the switch g contact 10, and out by the line d. To throw coils in multiple, which done motor has attained its normal. specs running/ills swi is thrown to right and the cirooitis as follows: Ernie 'he lino. passes to contact 4%, by Ll. e contact 3, through one of the coils S tooont ct 6, hy cross connection to centers- 3$, by or ch arm fto contact 7, by the cross connec neat atlino d. The second coil S is connected from the contact 5, the connection with r switch arm 9 contact 8, by thence out.

line 0 through contact the switch arsn j to cor ct 1 b he diagrams en iilnstzntive merely,

which a i ave and I do n the tracer may he or l switching at. Q

the arrang' of not in t on before referred to l A l l an alternating era, a transformer

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