US501081A - Electric-arc lamp - Google Patents

Description

(No Model) G. KIRKEGAARD.

ELECTRIC ARC LAMP.

,081. Patented July 11, 1893.

UNITED STATES PATENT OFFICE.

GEORG KIRKEGAARD, OF BROOKLYN, NElV YORK.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 501,081, dated July 11, 1893.

Application filed February 20, 1893. Serial No. 462,987. (No model.)

To whom it may concern.-

Be it known that I, GEoRo KIRKEGAARD,L citizen of the United States, residing at Brooklyn, in the county of Kings andState of New York, have invented certain new and useful Improvements in Are Lamps, of which the following is a full, clear, and exact description.

My invention relates to are lamps, the object being to produce a simple and efficient mechanism, and a cut-out whereby the carbons may be almost entirely consumed and then automatically cut out, resulting in a long burning of the lamp and a great saving of carbon.

A further object is to improve the carbon holder.

The invention consists of the details of construction which will be hereinafter described and particularly pointed out in the claims.

Referring to the drawings, Figure 1 represents a side elevation of the lamp, parts of which are broken away and other parts in section. Fig. 2 is a horizontal section of a portion of the lamp mechanism taken on the line 00, 0c of Fig. 1; and Fig. 3 is a sectional detail of the carbon holder.

In this lamp the upper carbon holder is mounted in a cross head which slides up and down on the side rods of the lamp, the cross head being suspended by a cord which winds and unwinds over a drum to regulate the lamp.

Referring to the drawings by letter, Arepresents an electro-magnet located in a shunt circuit to the arc. Its armature a is fixed to the end of a lever l), pivoted at b in a frame 0, projecting beyond the pivot and terminating in a bent up finger b. The lever has attached to it, a downwardly projecting arm 22 to which is attached a coiled spring b tending to lift the lever in opposition to the pull of the magnet. This spring passes through a circular opening in the lever. Two arms 11 project from the under side of the lever and support at their lower ends a shaft, upon which is mounted a roller b. The frame 0 consists of two uprights supported on the floor of the casing. In it is mounted a shaft 0, upon which is loosely mounted a drum 0 around which a ribbon (Z is coiled. One end of the ribbon is secured to the drum,

while the other passes over the roller 1), thence through a hole in the bottom of the lamp casing, around the roller 6, on the crosshead 6 and is finally fixed to the floor of the lamp casing. The drum 0 carries a ratchet wheel 0, rigidly fixed to shaft 0. The escapement wheel carries a pawl c which engages with the ratchet wheel. .lVhen the escapernent Wheel is free to turn, the weight of the cross-head e and its attachments acting through the ribbon d upon the drum 0 causes it to rotate through the engagement of the pawl. Upon the shaft is also fixed another ratchet wheel f, and between this ratchet and the drum 0 is loosely mounted a second drum f. This drum carries a pawl f which engages with ratchet f. hen the lamp is in operation or in its normal condition, the pawl f is held out of engagement with the ratchet, as shown in Fig. 2, by a pinion f or other suitable device, fixed to the frame 0. Hence when the cross-head e is moving downward, the drum f does not rotate, while the other devices on the shaft do rotate. The drum f contains a spring f one end of which is fast to a part of the frame and the other to the drum. The upright g which controls the escapement, carries a vibrating finger g, above which stands a loosely pivoted dog g which rests upon the finger of the main lever.

Each carbon holder is provided with an arm h of conducting material having a fusible metallic pin 77,, which holds under tension, a spring kg. The main circuit of the lamp includes both of these springs and the pins h and arms h. The fusible pins are located closely adjacent to the carbon pencils and at. a point where the consumption of the carbons should cease for the protection of the carbon holders. hen the arc has consumed one of the pencils down to the neighborhood of the fusible pins, its heat melts the pins and the spring 72. flies upward and breaks the circuit of the lamp, thus extinguishing the arc and preventing inj ury to the carbon holders. lVith these devices both carbons may be consumed down to within half an inch, or thereabout, of the carbon holder, whereas in common prac tice it is customary to trim the lamp when the pencils are from two to four inches long. My lamp, therefore, consumes more of the carbon and burns for alonger period than other lamps. It is furthermore obvious that the length of the carbon pencils with respect to each other, is not material, so far as the liability to injury of the lamp is concerned.

The carbon holder here illustrated is similar to that shown in my application for patent, Serial No.451,'753,filed November12,l892. It possesses an improvement over that holder however, in respect to the manner of secur ing it to the end of the carbon carrying rod. The shank "1 which enters the lower end of the tubular rod I is slit vertically and a screw 2" is passed into its end on the line of its axis, and after the shank has been inserted into the tube, the screw is driven in by means of a long slender screw driver passing through the tube, and the split sections of the shank are forced outward to hold it against the walls of the tube. Before the shank is inserted it is surrounded by a sleeve of insulating material j. hen the rod I is used in place of the cross-head and ribbon heretofore described, the circuit breaking spring It will be fixed at one end of the rod. Vhen the lamp is not burning, the carbons are separated. When the current is turned' on, magnot A becomes strongly energized and pulls down lever Z), thus lifting dog 9 out of engagement with the vibrating pallet of the escapement. The weight of the carbon and its carrier then causes it to move downward until the carbons are together, when the shunt magnet A becomes suddenly weak and spring I) lifts lever b, the roller b and the carbon pencils, and establishes the arc; simultaneously the escapement is locked. As the resistance of the arc increases, lever b is pulled down by the magnet and the escapement released, thus allowing the carbon to feed. When the upper carbon has been entirely consumed and it is desired to trim the lamp, the handle f is pulled downward, thus rotating shaft 0, winding up the ribbon d and lifting cross-head e to its most elevated position. The handle is then released and spring f reverses the roller and winds up the cord f The first movement of the handle f carries the pawl f out of engagement with the pinion f 3 and allows it to engage with ratchet f thus carrying the shaft with it, and on the return movement, the pawl f strikes pinion f just as the handle reaches the position in which it is shown.

It will be observed, that when the lamp is in operation, the pawl f is out of engagement with ratchet f and consequently the spring in the drum has no effect upon the shaft; therefore, the downward movement of the carbon holder is not affected by the spring and its feeding power remains constant throughout its entire movement. In

other ribbon lamps,there is usually provided a lightspring in the drum over which the ribbon winds and unwinds, the function of which is to take up the slack in the ribbon when the carbon holder is lifted to trim the lamp. This spring, therefore, is under more tension when the carbon holder is in its lower positions, than when it is elevated and the result is that the lamp feeds sluggishly at the end of the burning period, and too fast at the beginning thereof. My arrangement is therefore an improvement in this respect.

It is to be understood that my invention comprehends any form of circuit breaker which is operated by the heat of the arc, and myinvention is not confined to the spring and pin arrangement herein shown and described. A fusible strip of any character in the circuit of the lamp, may be located at any point where the heat of the arc will destroy it at a predetermined time.

Having thus described my invention, I claim 1. In an arc lamp, the combination with a hollow carbon rod, of a carbon holder having a split shank projecting into said holder and a screw or wedge entering the shank axially, to spread it and thus hold it in the rod, as described.

2. In an arc lamp, the combination of a pivoted lever carrying a pulley, a clock work and winding drum,the clock work controlled by the lever, an electro-magnet and a spring acting in opposition upon the lever, a carbon holder, and a cord connected with the carbon holder and leading over the pulley to the winding drum, substantially as described.

3. In an arc lamp, the combination of a movable carbon holder, a cord attached thereto, a winding drum for said cord, and means for manually winding said drum to lift the carbon holder, substantially as described.

4.. In an arc lamp, the combination of a cord or ribbon supporting the upper carbon holder, a drum around which said cord passes, a spring for winding the drum, and means for connecting and disconnecting the spring with the drum.

5. In an arc lamp, the combination with the upper carbon holder, of a cord or ribbon supporting the same and a winding drum, said cord or ribbon to be fixed at one end, thence passing around a pulley or turning post on the carbon holder, and thence to said winding drum, substantially as described.

In testimony whereof I subscribe my signature in presence of two witnesses.

GEORG KIRKEGAARD.

Witnesses:

WM. A. ROSENBAUM, FRANK S. Guns.

Images