US559407A - scribner - Google Patents

Description

2 SheetsSheet 1.

O. E. SORIBNER. ELECTRIC AR LAMP.

(No Model.)

No. 559,407. Patented May 5, 1896.

756; I m iowze ya.

AN DREW EGRAHAM. HUTD'LITKQWASHINGTO ILD c.

(No Model.) 2 SheetsSheet 2.

ELECTRIC ARC LAMP.

No. 559,407. Patented May 5, 1896.

y hllhlhhh 60 362260505 6 Q5 Zia/@2302;

jay zftta neya,

UNITED STATES PATENT OFFICE.

CHARLES E. SCRIBNER, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE \VESTERN ELECTRIC COMPANY, OF SAME PLACE.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 559,407, dated May 5, 1896.

Application filed December 30, 1893. Serial No. 495,221. (No model.)

To ctZZ whom it may concern:

Be it known that I, OHARLEs E. ScnIBNER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Automatic Cut-O uts for Are- Lamps, (Case No. 34:5,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to electric-arc lamps. Its object is to provide an automatic cut-out for such lamps adapted to be brought into operation by any abnormal increase of the resistance of the main circuit through the lampcarbons.

My inventionis especially applicable to arelamps of the type known as open-circuit lamps, in which the carbons are maintained in a separated relation during the idleness of the lamp and are brought together and subsequently separated to form the are when current finds circuit through the lamp. In such a lamp it is necessary that the cut-out shall be brought into operation in the event of any failure of the mechanism to cause the initial contact of the carbons, as the sticking of the carbon-rod in its bearings or by an abnormal increase in the resistance of the arc, and the cut-out must remain in position to shunt the lamp during the persistence of the abnormal condition. It is further desirable that the carbon-rod shall be released from the clutch of the fecdin g mechanism during the closed condition of the cutout, in order that the carbons may be permitted to come together as soon as they are free to do so to allow the lamp to resume its operation.

The essential elements of my improved cutout consist in a normally open cut-out circuit, including some resistance in shunt of the carbons, an electromagnet also in shunt of the carbons, an armature for the electromagnet controlling the continuity of the cut-out circuit, the armature being normally out of range of its electromagnet, and mechanism actuated by the feeding-magnet of the lamp to bring the armature into the range of attraction of its magnet. IV hen the feeding-magnet of the lamp is abnormally excited by the increased angle to a lug h of the frame 1).

current shunted through it on account of the abnormal resistance between the carbons, it operates to force the cut-out armature into the field of attraction of its magnet, which thereupon attracts it and closes the cut-out circuit. A slight current continues to flow through this cut-out magnet, since it is in shunt of a small resistance in the cut-out circuit, which, cooperating with the residual magnetism of the electromagnet, is suiiicient to retain the cut-out armature attracted and the cut-out circuit closed. In order that the carbon-rod may be free during this time, I may connect the feeding or clutch mechanism with this cut-out armature in such a manner that the carbon-rod is released from the clutch by the movement of the cut-out armature to its magnet, the feeding mechanism of the lamp being yieldingly connected with the clutch mechanism to permit this independent operation. It is obvious that the magnet which operates the cut-out and the feedingmagnet may be separate and distinct, but in practice I have preferred to use a single electromagnet for these purposes, this electromagnet being provided with two armatures working independently of each other.

My invention is illustrated in the accompanying drawings, and may be described with greater detail in connection With these illustrations.

Of the drawings, Figure 1 represents a side elevation of an arc-lamp equipped with my improved cut-out mechanism. Fig. 2 is a diagram showing the essential portions of the lamp and the circuit connections therewith.

One of the carbons a of the lamp is fixed in the usual manner in the bottom of the lampframe I). The other carbon to is carried upon a longitudinally movable rod 0, journaled in bearings in the upper portion of the lampframe I). The carbon-rod 0 moves through a clutch d of ordinary form, which is suspended by links from one arm of a bell-crank lever c, which is pivoted at its angle 6 to a lug upon the lamp-frame b. This lever c constitutes the cut-out lever. It is connected through a spring f with the extremity of another bellcrank lever g, which is also pivoted at its The other arm of the lever g is acted upon by a spring 2', whose force is thus transmitted through the lever g and the spring f to the lever c, moving the latter in a direction to lift the clutch d and the carbon-rod c. The lever g carries an armature g, moving before the poles of an electromagnet 7a, which is constructed to have high resistance and is connected in shunt of the carbons a a. This lever g, which thus controls the movable carbon through the medium of the spring f, lever e, and clutch cl, I term the feeding-lever. The cut-out lever 6 also carries an armature 6 which moves in a recess cut in the poles of the magnet 70. This recess is so formed that throughout the ordinary range of movement of armature 8 under the influence of the feeding-lever g, it is not sensibly attracted either up or down, so that it does not affect the operation of feeding; but when permitted to fall sufficiently low it comes within the range of attraction of the lower polar surface, at 7t, and moves toward it. The free arm of lever e is adapted to engage with a lever Z near its fulcrum Z. This lever carries a contact-point Z adapted to register with a contact-anvil m. The contacts Z on are ordinarily maintained in separated relation by a light spring n, acting upon the lever l. The contacts Z on control the continuity of the out-out circuit, the former being connected with the frame of the lamp and thus with the incoming main, and the latter with the outgoing main through a small resistance-coil 0.

In the idle condition of the lamp, the feed ing-magnet being inert, the carbon-rod cis grasped by clutch d and is raised by the pressure of the spring 71, as before observed. The armature e is at such a distance from the polar surface 7t of magnet 7c that it is not perceptibly attracted. The contact-points Z 'm are separated, thus opening the cut-out circuit. NVhen now currentis caused to traverse the lamp, magnet 70 is excited and attracts its armature g, lowering the system of levers g 6 until the clutch cl touches the floor or base of the lamp, and permits the carbon at to descend into contact with carbon d. hen these carbons touch, the magnet 70 is short-circuited and instantly loses its magnetism, permitting the system of levers g e to move toward their former position, thus causing the clutch to reengage the carbon-rod and again lift carbon to. The current through the carbons a a persist-s and creates an are between the carbon-points. The resistance of this are being considerable, however, a portion of the current is caused to be shunted through the high-resistance feeding-magnet 70, depending upon the length and resistance of the are between the carbon, so that the levers g e are not permitted to return to their idle position, but are kept in a state of unstable equilibrium, in which the force of the spring is balanced against the attraction of the magnet 74: for armature 9. As the carbons burn away and the resistance of the arc increases,magnet 70 becomes stronger and lowers the clutch (Z to reduce the length of the arc until finally the clutch touches the floor of the lamp and releases the carbon-rod. Then the operation is repeated as long as the carbons shall last. The recess in which the armature 6 travels is so formed and of such size that the armature does not come sufficiently near the polar surface 70 to be attracted during the normal range of vibration involved in the feeding of the carbons. hen the descent of the carbon-rod is arrested by the stop 0 coming against the lamp-frame, or by undue friction of the rod in its bearings, the magnet 7t continues to attract its armature g, after the levers have been lowered suiiiciently to cause the feeding of the carbons under normal conditions, until the armature e is brought into the range of attraction of the polar surface 7;. The armature c then moves to this polar surface, the spring f yielding to permit its motion. The downward extension of lever c is thus brought againstthe lcver Z, and the latter is moved against the force of the spring at, closing the contact-points Z m, and thus completing the cut-out circuit about the lamp. The magnet 7; is thus largely demagnetized, but sufficient current continues to flow through it to hold the armature e and maintain the shunt about the lamp. The feeding-armature g is, however, released and allows the lever g to fall back. It will be observed that the clutch is still in its lowest position and that the carbon-rod is free as to the clutch, lever 6 being still drawn down. The spring f is constructed to have just sufficient tension to carry the weight of the clutch mechanism, but not sufficient to detach armature e from magnet is. If now the carbon-rod becomes free from whatever obstacle has impeded its descent, it will bring the carbon a again into contact with carbon a, whereby the magnet 70 will be short-circuited. Having then lost its entire magnetization it will release armature e opening the cut-out circuit, and permitting the lamp to resume its operation.

Many modifications of my invention are possible without departing from its essential features, and I do not desire to be limited to the details of construction which I have shown and described; but

I claim as new and desire to secure by Let ters Patent- 1. The combination with an electric-arc lamp, of a cut-out circuit about the lamp, a normally-energized electromagnet, an armature for said electromagnet controlling the continuity of the out-out circuit, said armature being normally so far distant from the electromagnet as to be unattracted thereto, and mechanism actuated by the feeding-lever of the lamp to bring the said armature into range of its electromagnet under the influence of an abnormal resistance in the main circuit, substantially as described.

2. The combination with an electric-arc lamp, of a cut out circuit including resist IIO ance, a normally-energized electromagnet in shunt of the carbons, an armature for said electromagnet, controlling the continuity of the cut-out circuit, said armature being normally out of the range of attraction of its electromagnet, and mechanism controlled by the feeding-magnet of the lamp to cause or permit the said armature to be brought within the range of attraction of its electromagnet when the feeding-magnet is abnormally energized, substantially as described.

3. The combination with an open-circuit electric-arclamp, of a cut-out circuit therefor, an electromagnet in shunt of the carbons, an armature therefor controlling the continuity of the cut-out circuit, clutch mechanism connected with and controlled by the said armature, a feeding-armature controlled by an electromagnet in shunt of the carbons, and a yielding connection between said feeding-armature and the cut-out armature, said :teedingarmature being adapted when unduly attracted to bring the cut-out armature within range of its electromagnet, substantially as described.

4. The combination in an open-circuit arclamp, of a feeding-magnet and the feedingarmature thereof, an auxiliary cut-out ar1nature for the same electromagnet, normally out of the range of attraction of the electromagnet, clutch mechanism directly connected with the cut-out armature, a cut-out circuit controlled by the cut-out armature, a yielding connection between the cut-out armature and the feeding-armature, and a spring adapted to maintain the carbons normally separated, through the medium of the feeding-lever and the said yielding connection, substantially as described.

5. lhe combination in an electric-arc lamp, of an electromagnet in shunt of the carbons, an armature normally out of range of attraction thereof controlling the continuity of the cutout circuit, clutch mechanism suspended from said armature, a feeding-armature controlled by an electromagnet in shunt of the are, the cut-out armature being adapted to be brought into the range of the attraction of its electromagnet when the feeding-armature is abnormally attracted, and a yielding connection between the said armatures of such tension as to carry the weight of the clutch mechanism and the movable carbon, but not sufficient to resist the attraction between the cut-out armature and its magnet, substantially as described.

In witness whereof I hereunto subscribe my name this 18th day of December, A. D. 1893.

CHARLES E. SCRIBNER.

\Vitnesses:

ELLA EDLER, LUcILE RUssELL.

Images