US796467A - Electric-arc lamp. - Google Patents

Description

5 SHEETS-SHEET 1 PATENTBD AUG.-

B. A. STOWE. ELECTRIC ARG LAMP.

APPLIOA'I'IDE FILED D20. 5, 1902.

WJTNESSES' PATENTS!) AUG. 8, 1985.

B. A STOWB.

ELECTRIC ARC LAMP.

APPLIGATIDH EH-ED mm. 5, 1902.

5 SHEETS-SHEET 13 INVENTOR No. 796,467. PA TBNTED AUG. 8, 1905. B. A. STOWB.

ELEGTRIG ARC'LAMP.

APPLICATION FILED D30. 5, 1902.

5 SHEETS-SHEET 5 TNESSES fNVE TOR W 7 7 I Attorntjr UNITED STATES PATENT OFFICE.

BERNARD A. STOWE, OF CLEVELAND, OHIO, ASSIGNOR TO THE JANDUS ELBXTRIU COMPANY, OF CLEVELAND. OHIO.

ELECTRIC- Specification of Letters Patent.

ARC LAM P.

Patented Aug. 1905.

.To (M11 whom. I H'MLI/ UUILUVI'H/ Be it known that I, BERNARD A. S'rowu, a resident of Cleveland, in the county of Guyahoga and State of Ohio, have invented certain new and uscfullmprovements in Electric-Arc Lamps; and I do hereby declare the following to be a full, 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 improvements in electric-arc lamps, one object of the invention being to so construct the lamp that it will be readily adaptable for use on constant-potential circuits with currents ot'ditferentvoltage. either direct or alternating, and which can be readily converted from one type of arc-lamp to another and in accordance with the current or circuit (whether constant current or constant potential) with which it may be desired to use the lamp without altering or disturbing the general lamp structure.

A further object is to improve the lamp shell or casing and so connect it with the framework that it can be lowered bodily with the globe to expose the entire mechanism of the lamp.

A further object is to produce a general lamp structure which will admit of the removal of one regulating mechanism and the insertion of another.

A further object is to provide means to facilitate the insertion of upper carbons of dill'erent lengths into a holder within aguidetube.

A further object is to provide a support for a resistance-coil which can bercadily assembled and secured in place in the lamp structure and which can also be easily removed therefrom.

A further object is to so construct a resistance-coil as to minimize the extent of bearing' surface thereof against its support to facilitate ventilation of the coil.

A further object is to so construct and arrange a resistance-coil and its support as to insure adequate ventilation of said coil.

A further object is to provide improved controlling and regulating mechanism for an arc-lamp which can be used on constant-pd tcntial circuits of dilierent voltage and with director alternating currents.

A further object is to construct'and arrange the solenoids of the regulator in such manner that accurate alinemcnt of the cores with the bores oft-he spools will be insured under all conditions.

A further object is to provide simple means for adjusting the cores relatively to the coils of the solenoids according to the voltage on the circuit in which it may be desired to use the lamp.

A further object is to provide an improved air-pot for an arc-lamp-regulator mechanism.

A further object is to so construct the plunger of the air-potas to insure the uniform action of the same. I

A further object is to provide an air-pot construction in which the resistance exerted by the same to the movement of parts connected with it will not only be uniform, but can b: adjusted to suit the conditions existing in a lamp of a certain type and the character of the circuit in which it is placed.

A further object is to improve the construction of an electric-arc lamp in its various details and to render it capable and eflicicnt in the performance of all its functions.

With 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 1 is a sectional view of an electric-arc lamp cmbodying my improvements. Figs. Qand 3 are enlarged detail views, partly in section, showing the regulator mechanism. Fig. 4 is an enlarged plan view showing the regulator mechanism. Figs. 5 and 6 are views illustrating the air-pot construction. Fig. 6 is a view illustrating the manner of adjustingthe air-pot plunger. Figs. 7 and 8 are detail views of the clutch. Fig. 9 is a detail sectional view of the cap or hood of the lamp-casing. Fig. 10 is a detail view illustrating the resistancecoil and its support. Fig. 11 is a plan view illustrating a portion of the support for the resistance-coil. Figs. 12. 13, and 14. illustrate certain detail views. Figs. 15, 16, and 17 are diagrams of circuits for one hundred and ten volts, two hundred and twenty volts, and alternating-current circuits, respectively.

1 represents the main shell or body portion of the lamp-casing, having an enlarged upper portion 2 and an enlarged lower portion 3. The shell or body 1, with its enlarged ends is constructed of a single piece of sheet metal bent into cylindrical form and having its meeting edges permanently secured together by means of solder or otherwise. The intermediate portion of the shell is strengthened by a series of vertical corrugations 4, and the upper enlarged portion 2 is similarly strengthened by means of horizontal annular corrugations 4. A cap or hood 21 is disposed over the upper enlarged end of the shell or casing and provided with a peripheral flange 6, (preferably curved transversely,) which projects outwardly from the shell and acts as a watershed and also to preclude the entrance of dust and dirt into the casing. At diametrically opposite points blocks 7 are secured within the curved flange 6 of the hood, and each of these blocks is provided with a lug 8. The lugs 8 enter L-shaped slots 9, located at diametrically opposite points in the upper portion 2 of the shell or casing, and are normally prevented from escape from the horizontal arms of these slots by means of a thumb-screw 10, passed upwardly through the flange 6 and entering one of the slots 9 behind the lug therein. The shell or casing is thus connected with the hood by bayonet-joints normally locked by a thumb-screw 10. A bracket 11 is secured centrally upon the hood for the reception of an insulator 12, to which a link 13 is attached for the reception of suitable suspending devices. The only openings in the top of the hood are the holes 14 for the accommodation of the binding-posts for the leading-in wires. The metal of the hood surrounding the holes 14 is pressed outwardly to form flanges 15, over which caps 16 are fitted. These caps have inwardly-turned flanges at their upper ends, and on these caps binders 17 are seated and provided with depending flanges 18 to act as water-sheds, insulating material 19 bein g disposed between said binders and the caps 16. A block 20, located within the upper portion of the hood 21, is provided atdiametrically opposite points with perforated arms 22,seated against insulating material 23, disposed between said arms and the hood. Screw-bolts 24 are passed upwardly through the perforated arms 22 (but insulated therefrom) and enter threaded socketsin the binders 17. The central portion of the block is provided with an internally-threaded enlargement 25 for the reception of the threaded upper end of a tube 26, and said tube is prevented from turning by means of a screw 27. The tube 26 receives the upper carbon of the lamp, constitutes the backbone of the lamp-frame within the casing, and supports most of the mechanism, internal structure, and inner globe, as will be more fully hereinafter explained.

Returning now to the lamp shell or casing, attention is directed to an annular bead forming an internal groove 28 in the lower enlargement 3 of the shell 1, below which bead the enlargement curves inwardly and terminates in an opening 29. A cast-metal ring 30 is seated at its periphery in the groove 28, and its internal wall is engaged by the upper end of a cylindrical shell 31, the upper edge of which is spun over the cast ring, and immediately below said ring the shell-section 31 is made with an outwardly-projecting bead 32. The ring 30 is thus secured at its inner edge to the shell-section 31 and at its periphery to the enlarged lower end 2 of the main body portion 1 of the shell or casing. The cast ring 30 is provided with holes for ventilating purposes. The cylindrical shell-section 31 is provided at its lower end with a seat 33 for the outer globe, and at the juncture of said seat with the shell-section 31 notched brackets 34 are secured for the reception of the bails 35 of the globe-holder 36. The globe-holder 36 consists of a band of wire having eyes at its ends for the passage of a suitable bolt or other clamping device, and at diametrically opposite points said band is made with loops 37', with which the bails 35' have hinge connection. The globe-holder embraces the neck of the globe, and when the bails 35' are made to engage the notched brackets 34 the mouth of the globe will be held firmly against its seat.

From the construction and arrangement of parts above described it will be seen that when the upper end of the thumb-screw 10 is removed from the slot 9 in the shell or casing the latter after a slight turn can be dropped bodily, carrying also the outer globe with it and exposing the entire internal structure of the lamp. This not only gives free access to the interior of the lamp for trimming, but it also exposes the regulating mechanism, which can be readily adjusted or altered to accommodate currents of different voltage or to adapt the lamp for direct or alternating currents or even to remove one regulating mechanism and substitute another.

The lower end of the carbon-guide tube 26 extends through a threaded hole in the head 38 at the upper endof a cylinder 39, of cast metal, and projects partly through said cylinder. The cylinder and tube are prevented from turning relatively to each other by means of a screw 40 passing through the head of the cylinder and entering a hole in the tube. Amovable carbon-holder 41 is located within the tube 26 and has connected with it a flexible conductor 42, which is coiled within the tube and extended from the upper end thereof for connection with the regulating mechanism of the lamp. The carbon-holder 41 is provided on its upper end with a shank 43, which abuts against the closed head 14 ot the tube when a long carbon rod is forced upwardly into the carbon-holder in trimming the lamp. in some types of lamps, however, short upper carbons are used. For instance, in an alternating-current lamp an upper carbon eight or ten inches long is usually employed. It would not be convenientand,in fact,it would be practically impossible for the trimmer to press such a short carbon up into the tube far enough to cause the shank of the carbonholder to engage the head of the tube, and consequently a carbon of such short length could not be forced into the carbon-holder in this way. To provide forsueh acontingency, the devices now to be described may be employed. Atuhular screw 43' ispassed through the wall of the cylinder 39 and made to project into the latter. The other or plain end of the screw projects outwardly beyond the cylinder 39 and is made with an elongated slot 44'. A pin 45 is mounted to move ion gitudinally through the tube 43', and in alinement with this pin the carbon-tube 26 is made with a hole 46. A screw 47, projecting downwardly from a flange 48 on the cylinder, prevents the escape of the pin 45 from the tubular screw, and an arm 49 on the pin normally engages the end of the tubular screw to prevent the pin from entering the guidetuhe 26. Now when it is desired to insert'a short upper carbon the carbon-holder 41 is permitted to descend until the head 50 thereof has moved below the hole 46 near the lower end of the carbon-guide tube 26. The pin 45 is now turned until its arm 49 alines with the slot i l of the tubular screw, when the operator will press the pin forwardly and cause its end to pass through the hole 46 in the tube 26 and become disposed over the head of the carbonholder. The trimmer can now press the carbon into the holder, the pin 45 acting as an abutment for the latter. The short carbon having thus been pressed firmly into its holder, the trimmer will withdraw the pin 45 to the position shown in Fig. 1 to permit the carbon and its holder to move a proper distance upward in the tube.

The head 38 of the cylinder 39 bears against the lower face of a flanged sleeve 51, of yulcabeston or similar material, through which sleeve the carbon-guide tube also passes. An annular plate 52 is disposed upon the flange of the sleeve 51 and is made wit-h an integral collar 53-, embracing the sleeve 51. The plate 52 constitutes the clam p-floor and is secured in place by means of a series of screws passing through the plate (but insulated therefrom) and entering the flanged head 38 of the cylinder 39.

The lower end of the cylinder 39 is threaded externally for the reception of a collar 54, having lugs 55. A ring 56 is disposed below the collar and insulated therefrom, said ring being held in place by means of insulated screws passing through the lugs of the collar 5a and the flange of sleeve 51 and entering said ring 56. The arms of a depending bracket 57 are secured at their upper ends to the ring 56, and said bracket is provided at its lower end with a holder 58 for the lower carbon 59. The ring 56 is provided near its periphery at diametrically opposite points with holes for the passage of the upper ends of the arms of a depending yoke 60, the lower end of which carries a support 61 for the bottom of the arc-inclosing globe 62. The upper ends of the yoke-arms are threaded and pass freely through the holes in the ring 56, and above said ring thumb-nuts 63 are screwed on the yoke-arms, by means of which nuts the yoke can be adjusted to cause the upper end of the arc-inclosing globe to bear properly against its seaton the under face of the ring 56. Aside from the ring 56 the cover for the inner globe consists of a block 64 of porcelain or similar material having an annular flange 65 to rest upon a shoulder 66, formed in the ring 5.6, and also havingacentral hole for the passage of the uppercarhon. The uppercarbon passes loosely through the block 64, leaving suflicient space to permit the escape of gas from the inner globe to the cylinder 38, from which a portion of said gas may escape through a hole 67 in the cylinder-head,th rough which the cl utchrod passes. Air will also enter the cylinder 39 through the hole 87 and will mix with a portion of the air entering the latter from the inner globe. Now asthe temperature within the innerglobe rises the gas in said globe will increase in pressure and escape to the cylinder 39. where it will become diluted with air or become charged more or less with oxygen by the decomposition of the air, and when the temperature in the globe decreases (tending to producea partial vacuum) this diluted gas will be drawn-from the cylinder into the globe, these changes of temperature and consequent varying pressures within the globe being brought about'by the varying intensity of the are common in the practical operation of electric-arc lamps.

With a lamp structure-such as hereinbelt'ore described in detail various and, in fact, any form of regulating mechanism may be employed, according to the character of circuit and current with which it may be desired to use the lamp; but in this case I have shown and will describe regulating mechanism which can be employed on a constant-potential circuit with eithera direct or an alternating current. A detail description of the regulating devices will now follow.

A clamp 68, constructed to be removably secured .to the carbon-guide tube or backbone 26, is provided with a laterally-projectingarrn 69,to which a horizontally-disposed U- shaped spring 70 is secured at the juncture of its two arms. Each arm of the spring 70 is provided at its free end with a depending lug 71, from which the spools 72 of the regulatorsolenoid are pivotally suspended. To effect the free pivotal connection between the solenoid-spools 72 and the arms of the spring 70, bifurcated arms 7 3 are secured to the spools and terminate over the same, preferably in line with their axes. The members of the arms are provided with holes 74, and said members receive between them the lugs 71, which depend from the arms of the spring 70, to which they are pivotally connected by means of pins 75 passing through the holes of the arms 74 and holes in the lugs 71. The cores 76 of the solenoid are made laminated and connected at their lower ends by a cross-bar 77'that is to say, each lamina is made U- shaped, so that when all the laminae are secured togethera U-shaped core-frame will be produced the parallel arms of which will constitute the cores 76 and the portion connecting said parallel arms will constitute the cross-bar 7 7 The cross-bar of thecore'frame is mounted upon the upper member of an elliptical spring 78, and the lower member of said spring is secured to a lug 79, projecting laterally from a sleeve 80. A clutch-rod 81 passes through the sleeve 80 and also through the sleeve 51 and head of cylinder 39 and is attached at its lower end to the carbon-clutch 82, disposed over the porcelain block or cover 64:. This clutch is of the ring type and comprises a split ring 83, having ears 84 for the passage of a clamping-screw, and a ring 85, of steel, clamped in a groove 86 in said split ring and insulated from the latter by means of suitable insulating material 87.- That portion of the clutch-rod 81 which passes through the sleeve 80 is provided with a series of notches 88, and a pin 89 passes through a hole in the sleeve 80 and through one of said notches. By these means the sleeve 80, and consequently the solenoid-cores, can be adjusted vertically relatively to the spools according to the voltage of the line on which the lamp is to be used. By pivotally suspending the spools of the solenoids and mounting the cores on a spring in the manner above explained proper operative alinement of the bores of the spools and the cores is insured during the operation of the lamp and the jar and vibration incident thereto and binding of the coresin the spools is eifectually prevented,because the spools will always accommodate themselves to the cores, and vice versa. In order to avoid any possibility of the cores coming in actual contact with the wall of the bore of the spools, light and preferably soft cushioning material is placed on each core.

For the purpose of controlling the movement of the cores within the spools of the solenoids and to insure a slow and steady movement when the solenoids are acting to separate the carbons it has been common to use air-pots; but those heretofore in use have been found to be more or less defective in the accurate performance of the functions required of them. This defect is due largely to the employment of a plunger made in a single piece, which has to be made of sufiiciently less diameter than the internal diameter of the cylinder to permit the passage of a limited portion of air. In view of the fact that for the reason stated the plunger was necessarily of appreciably less diameter than that of the bore of the cylinder it has been found to be impossible to maintain said plunger concentric to the axis of the cylinder due to the jar and vibration of the mechanism of the lamp, and consequently at certain times a portion of the periphery of the single plunger will be in actual contact with the wall of the cylinder, while at a diametrically opposite point on the plunger it will be twice as far as it should be from the wall of the cylinder. Thus a duct is formed of such large size as to permit the too free How of air, and consequently the too free movement of the plunger and in turn the too sudden movement of the regulating devices and the carbon. For the reasons above pointed out the movements of the regulating mechanism due to the imperfections of the air-pot construction heretofore in use have been spasmodic and irregular. Furthermore, with a plunger made of a single piece the relative diameters of the plunger and cylinder must be such as to leave a very small space for the passage of air between said plunger and the wall of the cylinder; otherwise the proper cushioning effect would not be obtained. It has been found in practice that the interior surface of the cylinder and the external surface of the plunger will become more or less so corroded as to interfere with the thin annular air-duct between the plunger and' the wall of the cylinder and also to interfere with the proper movements of the plunger or cylinder relatively to each other. A construction is therefore desirable in which such interference by corrosion can be com pensated for, and this I accomplish in a manner which will be presently explained. An arm 90 is secured to the upper end of the clutch-rod 81 and projects laterally therefrom. Below the free end of this arm the cylinder 91 of the airpot is located, and the head 92 of this cylinder is provided on its inner face-with a seat 93 for a valve 94. The shank 95 of the valve passes freely through a hole in the head 92 and is pivotally attached at its upper end to the arm 90. In this manner the cylinder of the airpot is suspended. The plunger of the air-pot comprises a series of disks or laminae 96, constituting the plunger, and a plunger-rod 97, the latter being permanently secured at its lower end to the lamp-floor by means of a screw 98. The disks or laminae are made with alined holes for the accommodation of the plunger-rod 98, and each of these holes is of slightly but appreciably greater diameter than that of the rod 97, so that they will be capa- Isle of slight lateral movement, and the said disks or laminae each have a diameter slightly but appreciably less than that of the internal diameter of the cylinder 91. The several disks are maintained in contact with each other by means of a spring 99, encircling the rod 97 and bearing at its respective ends against the lower disk and the lamp-floor.

The upper disk of the series is secured to the plunger-rod preferably by riveting or upsettingthe upper end of the rod. Now experience shows that the disks will seldom, if ever, all be concentric with the plunger-rod and the bore of the cylinder at the same time; but. as a matter of fact, they will become variously disposed and the several disks will contact with the wall of the cylinder at various points, the locus of the contacting points being approximately equal to a circle marking the inner surface of the cylinder. The effect of this will be to cause the sectional plunger to contact with the wall of the cylinder approximately throughout the entire circumference, but the disposition of the disks form a tortuous duct for the passage of air, said duct having a capacity always equal to that of an annular duct which would be formed between the peripheral walls of the disks and the wall of the cylinderii' all of said disks (or a plunger consisting of a single disk) could be maintained disposed concentric to the plunger-rod and the axis of the cylinder. ThusI am enabled by the use of a plunger comprising a series of independent disks or laminae constructed and arranged as before described to insure the constant maintenance of a uniform action of the air-pot under all conditions, as well as a uniform and steady movement from one end of its throw to the other. Furthermore, I am enabled tomake each disk or lamina of appreciably less diameter relatively to the internal diameter of the cylinder than would be possible with a plunger made of a single piece, because the locus of the contacting points of the several disks with the wallof the cylinder will approximatelylie within a circle marked by the internal wall of the cylinder regardless of the diameter of each disk, and thus I am enabled to compensate for any interference by corrosion which would be encountered with a plunger made of a single piece, as before explained. It is apparent thatif the capacity of the tortuous duct above referred to as being formed by the irregular disposition of the disks within the cylinder be increased the resistance to the movement of the cylinder relatively to the plunger will be diminished, and thus the air-pot may be adjusted to offer greater or less mechanical resistance by adjusting the capacity of the said tortuous d not. This may be accomplished by separating certain of the disks by means of a washer 100 (see Fig. 6) of less diameter than that of the disks, the relative size of said washer to the diameter of the disks and the disposition of said washer between difierent pairs of disks controlling the size and capacity of the said tortuous passage from one end to the other of the series of disks. With the construction shown in the drawings the action of the solenoids will be-to raise the airpot cylinder (thus closing the valve at the upper end thereof) and cause the air-pot to act as above explained to resist the pull of the solenoids and insure the gradual rise of the upper carbon. When the cores of the solenoids descend, the air-cushion in the cylinder will cause the valve to open, the air to escape, and the cylinder to descend quickly. It is apparent that instead of making the cylinder of the air-pot movable it may be made stationary and the plunger connected with the regulating mechanism. In such case the disposition of the air-pot structure would be the reverse to that shown in the drawings and the spring 99 dispensed with, as the disks would maintain contact with each other by gravity.

Referring now to the lamp-circuits, it may be explained that current entering the lamp will flow from the positive binding-post by a conductor 101 to the solenoids and thence from the latter by conductor 102 to the upper carbon, thence to the lower carbon, thence through a conductor 103 and a switch 104 to a resistance 105, and finally to the negative binding-post of the lamp. If the lamp is to be used one constant-potential two-hundredand-twenty-volt circuit, the solenoid-coils will be included in series with each other, as shown in Fig. 16; but if it is to be used on a onehundred-and terrvolt circuit the solenoid coils will be included 'in parallel with each other, as shown in Fig. 15., the reason for this difference growing out of the fact that it is common in practice to employ five'amperes on a one-huudred-and-ten-volt circuit and two and one-half amperes on a two-hundred-andtwenty-volt circuit.

I have before explained that my lamp structure is adapted for use with the regulating mechanism herein described) on constant-potential circuits employing either direct or alternatiug' currents, and in order to transfer the lamp from a direct-current to an alternat ing-current lamp it is necessary to displace the resistancecoil 105 by an inductive resistance. The resistance-coil and'its support must therefore be readily removable, and I will now proceed to describe the construction and arrangement of the same and to point out certain advantageous features thereof.

The frame or support 106 for the resistancecoil consists of a series of externally-grooved segments of porcelain which when assembled make a complete ring having a series of circumferential grooves 10'? for the reception of the resistance-coil. Each segment is made with slots in the bases of the grooves for ventilating purposes, and the structure of each segment is strengthened by integral eross bars 108. The ridges between the grooves are notched, as at 109, to permit the resistance-coil to pass from one groove to another, and suitable provision is also made (such as perforated seats 110) for the attachment of binding-posts. The resistance-coil is so constructed as to minimize the extent of its contact with the support, so as to insure the greatest possible facility for ventilation. The resistance-coil is therefore formed irregulary, so as to present the appearance of a spiral groove 111, extending from end to end thereof, said groove forming a continuous air-duct and permitting the coil to bear only at intervals against the segmental support. The segmental porcelain support for the resistancecoil is located in the enlarged upper portion 2 of the shell or casing, and each segment is disposed upon a plate 113, and said plates are secured in turn to the hood 21 by means of bolts 114. By removing these bolts the segmental support will be released, and then by removing the resistance-coil the segments can be separated and removed from the lamp without disturbing the backbone 26 or any other part of the lamp structure.

From the above description it will be seen that the resistance device is split to permit it to be placed around or removed from around the central tube without the necessity of removing the hood.

IVhen the lamp is to be converted from a direct-current to an alternating-current lamp, it is simply necessary to remove the resistance-coil, as above explained, and insert in its place a resistance-coil 115 of any desired construction, as shown in the diagram Fig. 17.

Various slight changes might be made in the details of construction of my invention without departing from the spirit thereof or limiting its scope, and hence I do not wish to limit myself to the precise details herein set forth.

Havingfully described my invention, whatI claim as new, and desire to secure by Letters Patent, is

1. An arc-lamp structure comprising a central tube, a hood permanently secured thereto, split resistance and reactance devices, and means for interchangeably supporting the same in place in the lamp.

2. In an electric-arc lamp, the combination with a hood and internal framework supported thereby, of a sheet'metal shell havinga closed peripheral wall and means for removably connecting said shell to the hood, whereby said shell can be lowered bodily to expose the internal framework.

In an electric-arc lamp, the combination with a hood and internal framework supported thereby, of a sheet-metal shell removably attached to said hood, and an outer-globe holder supported by said shell.

4. In an electric-arc lamp, the combination with a hood, internal framework, regulator mechanism and an arc-inclosing globe supported by said hood, of a sheet-metal casing or shell removably attached to said hood, an outer-globe cover at the lower end of said casing or shell, and a holder for said outer globe supported by said casing or shell.

5. In an electric-arc lamp, the combination with a hood, of a plate secured therein, binding-posts upon said hood, screws securing the binding-posts to said plate, a backbone secured to said plate, and lamp mechanism connected with said backbone.

6. In an electric-arc lamp, the combination with a hood having two holes in its top and having flanges surrounding said holes, of a plate within the hood having portions entering said holes, insulating material between said plate and hood, sleeves mounted on the flanges on the hood, caps on said sleeves, and screws passing through said plate and sleeves and entering said caps.

7. The combination in an electric-arc lamp, of a central tube havinga lateral hole near its lower end, a carbon-holder and an adjustable pin adapted to enter the hole near the lower end of the tube and become'disposed over the carbon-holder to facilitate the insertion of a short rod of carbon thereinto.

8. The combination in an electric-arc lamp, of a central tube havinga lateral opening near its lower end, a carbon-holder in said tube, a tubular screw,means for supporting said screw in a horizontal position, a pin movable longitudinally through said tubular screw adapted to enter the hole in the central tube and be come disposed over the carbon-holder therein, and means for retaining said pin in its withdrawn position.

9. The combination in an electric-arc lamp, of a central tube having a hole near its lower end, a carbon-holder in said tube, a tubular screw, means for supporting said screw in a horizontal position in line with the hole in the central tube, a longitudinally-movable pin in said tubular screw, and a stop to be engaged by the outer end of said pin.

10. The combination in an electric-arc lam p, of a central tube having a lateral hole near its lower end, a tubular screw, means for supporting said tubular screw in a horizontal position in line with the hole near the lower end of the central tube, said tubular screw having a slot in its wall, a pin movable longitudinally in said tubular screw, and an arm on said pin to normally engage the end of the screw and pass through the slot therein when said pin is moved to enter the lateral hole in the central tube.

11. In an arc-lamp, the combination with a central tube or backbone, of an annular sectional support embracing said central tube or backbone and supported by the latter, and a resistance-coil wound upon said annular sectional support.

12. The combination in an are-lamp, of a coiled resistance-wire, and a sectional support therefor on which said resistance wire is wound, the sections of said support being detachably connected together and to the lamp structure.

13. In an arc-lamp, the combination with the frame, and a series of plates, of a resistancemace? 7 supporting device comprising several removable segments mounted, respectively, on said plates, boits securing said plates to the frame and a resistance-wire wound on said segments.

14. In an arclamp, the combination with the central tube or backbone and a plate secured to the upper end thereof, of a series of plates disposed below said first-mentioned plate, a segmental ring of insulating material having its segments mounted on the series of plates, and removable bolts securing the said series of plates to the plate secured to the central tube or backbone of the lamp.

15. In an arc-lamp, the combination with a regulator-magnet and a clutch, of a connecting device between the regulator-magnet and the clutch, a retarding device comprising a cylinder and a plunger consisting of a series of independent sections, one of said parts of the retarding device attached to a fixed support and the other part attached to the said connecting device,

16. In an arc-lamp, the combination witha clutch-rod and a regulator-magnet connected therewith, of an arm projecting laterally from said clutcha-od, an air-pot cylinder, a valve in the upper end thereof connected with and suspended from said arm, a plunger in said cylinder, and a fixed support for the plungerrod of said plunger.

17. in an arc-lam p, the combination with a clutch-rod and a regulator-magnet connected with said rod, of an arm projecting laterally from said rod, an air-pot cylinder, a valve in the upper end of said cylinder attached to and suspended from said arm, a plunger-rod, and a plunger on said rod comprising several independent laterally-movable disks, a fixed support for said plunger-rod and a spring between the lower disk of the series and said fixed support.

18. A clutch for an arc-lamp, comprising an annular frame having an internal annular groove, ears projecting from the meeting ends of said frame, a ring disposed within the grooved frame, insulating material between said ring and frame and a. fastening device passing through the ears of the frame.

19. In an electric-are lamp, the combination with regulator-magnets and their cores or armatures, of a. clutch, a clutch-rod, a eonnec tion between the cores or armature", of the regulator-magnets and the clutch-rod, an airpot cylinder suspended from said clutch-rod, a plunger comprising independently-movable disks in said air-pot cylinder, a plunger-rod on which said disks are loosely mounted and a fixed support for said plunger-rod.

20. In an electric-arc lamp, the combination with a central tube or backbone, of a clamp secured thereto, a spring-plate secured to said clamp and regulator-magnets secured to the free ends of said spring-plate.

21. In an electric-arc lamp, the combination witha central tube or backbone, of a U-shaped spring-plate embracing said central tube or backbone, and regulator-magnets suspended from the free ends of said spring-plate.

22. In an electric-arc lamp, the combination with a central tube or backbone and arms projecting laterally therefrom, of helices pivotally attached to and suspended from said arms, a yielding supported core-frame and sleeves of soft material on the arms of said coreframe.

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

' BERNARD A. STOWE. Witnesses:

ROBERT F. LAG'ANKE, FRANK A. Roonns.

Images