US550574A - Electric-arc lamp - Google Patents

Description

(No Model.) 3 SheetsSheet 1.

T. E. ADAMS.

ELECTRIC ARC LAMP. v No. 550,574. Patented Dec. 8,1895.

(No Model.) 3 Sheets-Sheet 2.

T. E. ADAMS.

ELECTRIC ARC LAMP. v

No. 550,574. Patented 1360.3, 1895.

UNITE STATES PATENT OFFICE.

THOMAS E. ADAMS, OF CLEVELAND, OHIO.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 550,574, dated December 3, 1895.

Application filed March 14, 1895. Serial No. 541,732. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS E. ADAMS, a resident of Cleveland, in the county of Guyahoga and State of Ohio, have invented certain new and useful Improvements in Electric-Arc Lamps; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in electric-arc lamps designed more particularly for use on constant-potential circuits, one obj ect of the invention being to so construct the lamp that its adjustments will remain certain and fixed more permanently than has been heretofore common in the art.

A further object is to produce devices so constructed and arranged as to prevent the lapping of the carbon points, which would produce a short circuit and result in either blowing the fuse on the line when such a large current is permitted to pass as would dangerously heat the conducting-wires or preventing the lamp from burning until the carbons are placed in proper alignment and the damage to the fuse or line repaired.

A further object is to so construct the friction-clutch which grasps the carbon rods that it shall have maximum durability.

A further object is to construct the clutch in such manner that its liability to be affected by dust and dirt will be reduced to a minimum.

A further object is to so construct the clutch of an electric-arc lamp that a carbon rod not perfectly smooth and true 011 its surface will be properly fed and so that it shall be convenient of adjustment in the lamp and compensate for wear of the carbon rod or other parts.

lVith these objects in view the invention consists in certain novel features of construction and combinations and arrangements of parts, as hereinafter set forth, and pointed out in the claims.

In the accompanying drawings, Figure l is a diagrammatical view illustrating my invention. Fig. 2 is an elevation. Fig. 3 is a horizontal sectional view. Fig. 3 is a section on the line as so of Fig. 2. Figs. 4, 5, 6, and '7 are detail views.

A A represent the top and bottom plates of the lamp-frame, connected together and properly spaced apart by means of standards A A and B represents the chimney. A tube a is connected with a plate a, secured to the top plate A of the lamp-frame and extends up through the chimney B. The upper end of the tube a is screw-threaded for the reception of a nut a below which a cap a is located, said cap having a bearing on a ring a, 7

attached to the upper end of the chimney, and the ring a is made with recesses for the positive and negative leading in wires and A metallic tube 1) surrounds the tube a and is electrically separated therefrom by means of insulating material Z). A coil O, of German silver or other resistance material, is wound about the tube 1) and insulated from said tube by means of interposed strips b preferably of asbestos. The coil 0 is so wound that its convolutions will not be in contact with each other, and to the upper end of the coil the leading-in wire is connected. To the lower end of the resistance-coil a conductor a (com posed, preferably, of strands of fine wire) is connected. The upper end of the conductor 0 is connected with a spring plate or adjuster 0, adapted to partially embrace the resistance-coil and have a slide-wire contact with the convolutions of the coil. By moving the plate or adjuster 0 up or down the amount of resistance to be included in the lamp-circuit can be readily adjusted.

As shown in Fig. 2, the flexible conductor 0 can be made to move about the resistancecoil, so that when the contact-plate is moved up or down and partially rotated about the resistance-coil the slack in the conductor can be compensated for.

A metallic bracket d is secured to the inn der face of the top plate A of the lamp-frame and insulated therefrom, said bracket being electrically connected with the lower end of the metallic tube 1) by a short conductor (1, and to the upper end of said metallic tube the -l leading-in wire is connected.

Fine-wire electromagnets D D are secured to the upper plate of the lamp-frame and depend therefrom. The poles f of the electromagnets D project some distance below the spools and are made with inner flattened faces f, between which an armature E is disposed, said arn'iature being preferably a rectangular block of iron, which also constitutes a weight, for a purpose hereinafter explained. In other words,the electromagnets D are provided with a weighted armature.

The armature E is carried by an armaturelever E, which comprises a transverse shaft g, mounted at its ends in suitable lugs projecting from the standards A and arms g, the armature being secured to the free ends of the latter. An arm or bracket g is secured to the opposite side of the armature E, and to the free end of said arm the lower end of a plunger-rod g is pivoted, the plunger connected with said rod operating in an air-pot g pivotally connected with the top plate A of the lamp-frame.

To the bottom plate A of the lamp-frame and at the opposite side thereof from the finewire magnets D D a coarse-wire magnet F is secured, the poles h h of said magnet F being located at the ends of the core and projecting forwardly from the spool. Between the poles h h an armature F is disposed and secured to lugs i, projecting from the shaft 9 of the armature-lever, said lugs being located on the opposite side of the shaft from the arms g.

The top and bottom plates A A of the lampframe are perforated for the accommodation of the carbon or lamp rod G, said rod also passing through a perforation in the bracket (Z and into the tube a. A contact plate or brush j is secured to the plate or bracket (1 and bears at its free end against the carbon rod for conduetin g the current thereto. The plate or bracket (Z is also electrically connected with one end of one of the fine-wire coils by means of a spring or spiral conductor K, the free end of the other fine-wire coil bein g connected with a conductor K by a short spring orspiral conductor K One end of the conductor K is connected with the lower-carbon holder of the lamp and the other end is connected with one end of the coil of the coarse-wire magnet F, the other end of said coil being connected with the lower end of the resistanee-coil O by a wire Thus it will be seen that the coarse-wire magnet is included in the main circuit in series and the fine-wire magnets included in series with the coarse-wire magnet, but in a shunt-circuit around the are.

In tracing the main circuit through the lamp it will be seen that the current enters at and passes through the tube I), then through the conductor (Z to the bracket (1, then to the carbon or lamp rod G through the contact plate or brush j, thence through the upper carbon to the lower carbon, thence through the latter and its holder, and thence through the conductor K to one end of the helix of the coarse-wire magnet. From the other end of said helix the current passes through wire 70 to the resistance-coil C, then through the conductor 0 and plate 0, and then through more or less of the convolutions of said coil 0, and finally out at The path of the shunt-circuit will be traced as follows: From the bracket d a portion of the current will pass through the spring or conductor K, then through the helices of the fine-wire magnets, and then by the conductor K to the wire K, which latter is connected with one end of the helix of the coarse-wire magnet.

The carbon or lamp rod G passes through a clutch device H, the construction of which will now be explained. The saddle 1 of the clutch embraces the carbon rod G and is so constructed as to have an extended bearing thereon. From opposite sides of the saddle ears 2 project, between which the clutchlever 3 is eccentrically pivoted by means'of a pin a, and at its pivoted end is bifurcated for the reception of a clutch-shoe 5, which is pivotally connected to said lever by means of a pin 6 passing through the contracted upper end of an angular or square-cornered slot '7, made in the shoe 5, the pin 4:, which pivots the lever to the ears of the saddle, passing through the larger end 8 of said slot. Thus it will be seen that the shoe 5 will be permitted to move on its fulcrum a distance permitted by the width of the wider portion of the slot 7, which will be sufficient to cause the clutch to grasp or release the carbon rod. If a round pin 6 be passed through a round hole 00 in the shoe 5 of larger diameter than the pin, the normal position of rest will be as shown in Fig. 7, and when strain is applied the position of the pin in the slot would be as shown in Fig. 6. This change of position is lost motion, which is very undesirable in a clutch device for an electric-arc lamp. By making the portion of the slot 7 through which the pin 6 passes angular, as shown in Fig. 5, the position of the pin in the angular slot '7 will always be the same, either for position of rest or strain, and, again, by making the slot 7 in the manner above explained clogging by dust and dirt will be prevented. My improved clutch presenting such a long gripping-surface, a dent or enlargement on the lamp or carbon rod will not affect the proper operation of the clutch in the least. The free end of the clutch-lever 3 is pivotally connected to an arm 0, which latter is pivotally connected between the lugs or ears '5 on the shaft g, the clutch-lever thus being in effect connected with the armature-lever E. To the saddle 1 of the clutch a trip-arm 10 is connected and adapted to engage the bottom plate A of the lamp or a plate 11 secured thereto to release the clutch, as hereinafter explained, said trip-arm havin an elongated slot 10 for the reception of a screw 10 ,whereby to admit of the ready adjustment of said trip-arm.

In the diagrammatical view, Fig 1, the carbons are shown separated, as when the lamp is not burning. \Vhen the current is switched on, its only path will be through the fine-wire magnets, which at once draw up the weighted armature E, slowly lowering the clutch and carbon rod until the carbon points come into contact. If the trimming of the lamp is regular the carbon points will come together before the clutch releases the carbon rod. Consequently the carbon cannot lap, (a common trouble with constant-potential lamps.) The instant the points touch a path for the current will be closed through the helix of the coarse-wire magnet F, which latter will attract the armature F (overcoming the pull of the fine-wire magnets E) and lift the clutch, which again separates the carbons and establishes the arc. The pull of the fine-wire magnets is nearly constant and the strength of the coarse-wire magnet varies with the resistance of the arc. As the carbons burn away, the resistance of the arc increases, and conse quently the current flowing through the coarse-wire magnet decreases until the finewire or shunt magnets overcome its pull and slowly lower the carbon rod, thus maintaining the arc until the trip-arm 10 of the clutch reaches the plate 11 or the bottom plate A of the lamp-frame and releases the clutch. This allows the carbon rod to slide downwardly a little, but it will be instantly caught and raised by the clutch, because'the approach of the carbons toward each other allows an increased current to pass through the coil of the coarse-wire magnet. IVhen the carbons shall have been consumed, the circuit will be opened at the arc of the first pair of carbons (when several lamps are in the circuit) that can feed no more, and the carbons in another lamp that are notyet consumed will continue to touch and spark slightly, thus indicating that it is the dark lamp which needs trimming.

No harm will result if lamps are allowed to remain untrimmed and the only loss will be the slight current passing through the finewire coils until the current is opened atthe switch. Experience has shown that no cutout is needed, as the resistance of the fine-wire coils is sufficient to prevent burning out in case of accident to the carbons.

My improvements combine in the produc tion of an electric-arc lamp which is simple in construction and effectual in all respects in the performance of its functions.

Various slight changes might be made in the details of construct-ion of my invention without departing from the spirit thereof or limiting its scope, and hence I do not wish to restrict myself to the precise details of 0011- struction herein set forth; but,

IIa-ving fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an electric arc lamp, a clutch comprising a saddle adapted to bear against the carbon rod and having ears projecting beyond the same, a bifurcated lever pivoted be tween said ears and a shoe pivoted in said lever and adapted to bear against the carbon rod, substantially as set forth.

2. 111 an electric arc lamp, a clutch comprising a saddle adapted to embrace the carbon rod, a clutch lever having a bifurcated end pivotally connected to said saddle,a clutch shoe pivoted in said bifurcated end of the lever, said shoe having a slot made larger at one end than at the other, the pin which pivots the shoe to the lever passing through the smaller end of the slot and the pin which pivots the lever to the saddle passing through the larger end of the slot, substantially as set forth.

3. In an electric arc lamp, a clutch comprising a saddle adapted to embrace the carbon rod, a clutch lever eccentrically pivoted to said saddle, and a clutch shoe pivoted to said lever, substantially as set forth.

4:. In an electric arc lamp, the combination with a carbon rod, an electro-magnet and an armature for said electro-magnet, of a clutch comprising a saddle adapted to embrace the carbon rod, a clutch lever eccentrically pivoted to the saddle, a connection between said clutch lever and said armature, and a clutch shoe pivoted to said clutch lever, substantially as set forth.

5. In an electric lamp,the combination with the chimney thereof of a metallic tube located therein and constituting a conductor, and a resistance coil inclosing said tube and insulated therefrom,substantially as set forth.

6. In an electric lamp the'combination with a metallic tube, of a resistance coil inclosing the same and insulated therefrom, an elastic plate having a slide wire contact with said resistance coil, and a conductor for connecting said plate with one end of the resistance coil in such manner as to permit the elastic plate to be moved about said coil to take up slack of said conductor, substantially as set forth.

7. In an electric arc lamp the combination with a frame and a chimney, of a tube secured to the frame and extending through the chimney and having a screw threaded upper end, a flaring ring at the upper end of said chimney, a cap having a bearing in said ring and a nut on said screw threaded upper end of said tube bearing on said cap, substantially as set forth.

8. In an electric arc lamp, a clutch comprising a saddle adapted to embrace the carbon rod, a clutch lever having a bifurcated end pivotally connected to said saddle, a clutch shoe pivoted in said bifurcated end of the lever, said shoe having a square cornered slot made larger at one end than at the other, the pin which pivots the shoe to the lever passing through the smaller square cornered end of the slot and the pin which pivots the lever to the saddle passing through the larger end of the slot, substantially as set forth.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

THOS. E. ADAMS.

Witnesses LEWIS H. RoeERs, A. D. DORMAN.

Images