Патент USA US2285450код для вставки
June 9, 1942. 2,285,450 H. J. MCCARTHY ELECTRIC DISCHARGE LAMP AND STARTING DEVICE Filed May 18, 1940 llllllllll nun-""1"."-“nn-nn-u-nnumnvununnnIn-unllnnnnnnnnn-.n., ?nnu?ununununllnununununan‘: u llll Illnllnl-IIIIIII HENR] JHcCARTI/j ‘ INVENTOR, MATTORNEY. ( r 2,285,450 Patented June 9, 1942 UNITED STATES-PATENT OFFICE 2,285,450 ELECTRIC DISCHARGE LAMP AND STARTING DEVICE Henry J. McCarthy, Danvers, Masa, assignor to . Hygrade Sylvania Corporation, a corporation of Massachusetts Application May 18, 1940, Serial No. 335,968 5 Claims. (Cl. 176-124) The present invention relates to electric gase ous discharge lamps and in particular to appa ratus for starting and operating such lamps. An object of the invention is to provide a start wires n. The remaining ends n and n of each. ' ?lament may be connected together through the resistance It. A condenser 9 may be placed across the resistance It to cut down radio inter ing apparatus for electric gaseous discharge C1 i'erence due to the operation 01 the switch and ' lamps which will allow the cathodes of the lamp to be preheated before the discharge is started between them. Another object is to provide a starting appa lamp. A condenser of .006 microfarad has‘ proven to be advantageous. A bimetallic strip 20 is connected at one of its ends to an end of the resistor l3. The other end ratus which will be so timed in its action that no 10 of the resistor I3 is connected to a contact 25 placed near the other end of the bimetallic strip. greater interval of time will be used for the pre The direct circuit between the moving end of the heating of the cathodes than is absolutely nec essary. bimetallic strip and the contact 25 is normally _ A further object is to provide a switch which will accomplish the above-mentioned objects and at the same time function under all possible con open. Another contact, however, is also con nected to the same end of the resistor I! through the additional resistance 3| and arranged to be normally closed to the moving end of the bi metallic strip. The resistance 3| is very small compared to the resistance IS. The latter may ditions of starting and restarting. 'A feature of this starting apparatus is that it eliminates the unnecessary time lag present in many switches during the starting and restart 20 be about 40,000 ohms while resistance 3| is only about 1 to 5-ohms. The resistance 3| is placed ing period. in a position so as to heat the bimetallic strip, Other objects, advantages and features will be and is preferably made part of the contact 20 by apparent from the following speci?cations taken making the contact of carbon for example. in conjunction with the accompanying drawing Figures 2 and 3 show the arrangement of the in which: . starting apparatus more in detail. A resistance Figure 1 is a schematic diagram of the ar rod I3‘ is suspended between the two lead-in rangement of apparatus according to the inven wires l8 and I9. A supporting arm 2| extends inwardly from lead-in wire I! and attached to Figure 2 is a side view of the switching device the inward end thereof is a bimetallic strip 20, according to the invention. which is bent around the resistance rod. The Figure 3 is a cross-section view of a part of the resistance rod may have an insulating coating switching device according to the invention. tion. ' - Figure 4 is a side view of a method in which the switching elements may be connectedwith the lead-in strips. Figure 5 is a side view of the preferred method in. which the switching elements may be con thereon of , for example, alumina and shellac, 29. Two lead-in strips 23 and 24, one with a low . resistance contact point, for example, silver 25 attached to its free end, and the other with a high resistance contact point, for example, car nected with the lead-in strips. In Figure 1, an electric gaseous discharge lamp bon or some other material 26, attached to its free end, are ?xed at a common source 21 on the 4 sealed at each end. The glassenvelope may direction of the free end of the bimetallic strip 20. The high resistance contact is normally in a closed position in relation to the strip 20 and the low resistance contact is in a normally open posi ' I has the glass envelope 2 with electrodes 3 ‘and 40 lead-in wire l9, and project upwardly in the have a coating of ?uorescent material 5 on its inner wall. The electrodes 3 and 4 may be coils of tungsten wire coated with one or more of the alkaline earth oxides to increase the electron ,emission, with the auxiliary electrodes 6 and '1 to aid in starting. An atmosphere of inert gas, tion in relation to the strip 20. - The whole unit may be sealed into a container 28 of metal, glass, or the like. If the unit is such as argon, and also a vapor, such as mercury, sealed in a metal container, the lead-in wires may be sealed in the glass envelope. A lead-in wire 8 from one end of one ?lament may be con 50 must, of course, be insulated therefrom. Since the high resistance contact is normally nected to one end of the power line from which in a closed position in relation to the bimetallic the apparatus is operated. An end of the other strip 20, the filaments 3 and 4 will start heating ?lament may be connected through a suitable and the high‘reslstance contact 26 and the bi ballast impedance, such as an inductance coil I0, to the other end of the power line by the lead-in metallic strip 20, with which it is in contact will 2 2,295,450 start ‘heating when the voltage is turned on. ' The high resistance contact point and the. bi metallic strip are so proportioned that they will become su?lciently hot to - break contact with each other at about the same time that the ?la» low resistance contact point 25 on the end of the lead-in strip 23, thus short-circuiting the resist ance rod and start the preheating of the ?la ments of the lamp. . Figure 4 shows a manner in which the switch ments are su?lciently heated to start the dis ing elements may be. connected, wherein lead charge across the lamp. in strip 24, is, bent away” from its, extension along . . The contact point ‘26 is a high resistance con tact, compared with the silver contact 25, but is lead-in strip 23' from pointjl. A low, resistance contact 30 is attached tothe free end vof the of a low resistance say 1 to 5 ohms, as compared 10. strip 20 and contacts the point 25 when the aux with the resistor l3, which may be 40,000 ohms., Thus with the carbon contact closed, the resistor I3 is e?ectively short-circuited and the normal iliary starting feature of the apparatus is em ployed. - t , ~ " Figure 5 shows the preferred manner in which heating current ?ows through ?laments 3 and 4; , the‘ switching elements may be connected, where but the carbon contact has nonetheless a resist 15 in theiree endfof lead-in strip 24 is bent back ance su?icient to heat the bimetallic strip 20 for a short distance in a U-shaped manner so as enough to cause it to break contact at the proper to cause the high resistance contact 26 attached time. My invention eliminates, the unnecessary thereto to become located in contact with the time lag present in other switches, namely the ‘bimetallic strip 20 at a point opposite contact 30. time which elapses between the placing of the 20 The low resistance contacts 30 and 25 are re line voltage across the lead-in wires and the spectively located at the tip of the bimetallic starting of the preheating of the ?laments. , In strip 20 and on the side of the lead-in strip 24 my invention, by reason of the normally closed ‘ at a point opposite contact point 30. In the position of the high resistance contact point in present vmodi?cation, the lead-in strip 24 is it relation to the bimetallic strip 20, the line voltage 25 self a bimetallic strip to compensate for ambient _ is immediately placed across this contact and as temperature changes. The strip 24 is placed to a result, the heating of the ?laments takes place _ move with ambient temperature in the same di immediately. . ~ rection as the strip 20. The contacts 25 and 26 If, for any reason, the discharge does not take then move with ambient temperature in the same place across the lamp when the bimetallic strip 30 direction that the strip 20 moves, and if the length 20' breaks from its contact with the high resist of the strip 24 is properly adjusted, they move ance contact point 26, my invention provides a out, not only in the same direction but also the unique auxiliary starting apparatus. ‘ If the dis same amount, so that the operation ofthe switch charge fails to take place, the resistance rod l3 remains constant. ‘ will become heated as a result of receiving the At the same time‘, the bent back portion of the full line voltage. The heat from the rod will strip 24 in the neighborhood of contact 26, being heat the bimetallic strip 20, causing it to bend bimetallic, moves oppositely to strip 20 when towards the low resistance contact point 25 on the end of the lead-in strip 23. ‘The low resist ance contact 25 and the bimetallic strip 20 are 40 so spaced that contact will be made when a voltage is placed across the rod I3. When this» contact has been established the resistance rod will be short-circuited, the rod and the strip will start to cool and the ?laments of the lamp will start to warm up. The contact 25 and the strip 20 are so proportioned that they will have cooled to a point where they will break contact at about the same time the ?laments are hot enough to ' start a vdischarge across the lamp. When this contact is broken, the bimetallic strip will move away from its contact with the low resistance contact point. Since there is about one-half line voltage across ' the resistance rod during the operation of the lamp, the heat conducted to the bimetallic strip by the rod will cause the strip to take a position. 1 during the actual operation of the lamp, at a both are heated by passage of current through the carbon 26, thus giving a quicker and cleaner break in contact. Thus this construction of ele-_ ment 24 has a double advantage. . The resistance rod should have a high ~resist ance, say 40,000 ohms. For this resistance, I ‘have, for example, used a graphite rod, 0.45 inch long and 0.025 inch in diameter. For my high resistance contact I have used carbon, having a resistance of about 1 to 5 ohms. For my low re sistance contact I have used silver, having a re sistance of a fractional part of an ohm. Al though I have used these particular materials, my invention does not necessitate the use of these exact same materials. It is sufllcient that a high resistance contact point, a low resist ance contact point and a high resistance rod be used. . Certain speci?cations with regard to the lamp must be used in order to obtain the results in the switch action described above. The lamp point about one-half between its normally closed position with the high resistance carbon contact, ' ‘ must have a gas pressure and electrode spacing, and the low resistance contact point. Thus there 00 and a tube diameter such that when the elec trodes are cold, no substantial discharge will is no danger of the strip 20 cooling to a tem take place between the electrodes at the line volt perature where it would re-establish its contact age used. " . ‘with the’ high resistance contact point, and thus What I claim is: renew the starting operation. 65 1. In combination: an electric gaseous dis If the current should be thrown off and im charge lamp having at least two electrodes, one mediately turned on again, without a su?icient at least of said electrodes being of the ?lamene time elapsing to allow the strip 20 to cool su?l tary type; a ballast impedance in series with said .ciently to re-establish' its contact with the high resistance carbon contact point, the auxiliary 70 lamp; a resistor connecting one end of a ?la mentary electrode to the other electrode, said starting apparatus will act as the principal start resistor having an impedance which is large com ing apparatus, i. e., the line voltage would then pared with that of the ballast impedance; a high bev across the resistance rod and the strip 20 resistance contact; a low resistance contact; a would be heated to such a temperature that it would bend back and make contact with the 75 bimetallic strip electrically contacting said high resistance contact when said resistor is unener 2,285,450 gized and in a position to be distorted by the heat developed in said high resistance contact when the latter passes current, and, to open said contact when distorted sumciently; said bime tallic strip also being so positioned as to be dis- ‘ torted by the heat developed in said ‘resistor when the latter passes current and to short circuit said resistor, by making contact with the low resist ance contact, when distorted su?iciently. _ 3 contact being connected to said other end of said resistor through a second resistor in proximity to said bimetallic strip. , 4. A relay for controlling the preheating of the ?laments of an electric gaseous discharge lamp, said relay comprising: a resistor; a bimetallic strip in position to be distorted by heat from said resistor and having one end electrically con nected to one end of said resistor; a low' re 2. The combination of claim 1 in which: The 10 sistance contact connected to the other end of said resistor and near but out of contact with ballast impedance is such that the operating the other end of the bimetallic strip when said re voltage of the lamp, after the electrodes have sistor is unenergized; and a second contact closed been heated, is much lower than the starting to said other end of said bimetallic strip when voltage when the electrodes are cold; and‘in - said resistor is unenergized, said second contact 15 which the resistor connected between the lamp being connected to said other end of said resistor electrodes is positioned so that the heat produced through a second resistor'in proximity to said bi in it by the operating voltage of the lamp is in metallic strip. ‘ suf?cient to distort the bimetallic. strip, with 5. A relay for controlling the preheating of which it is in‘ contact, enough to short-circuit the ?laments of an electric gaseous discharge said resistor, but so that the voltage necessary 20 lamp, said relay comprising: a resistor; a contact for short-circuiting is nevertheless below the of high resistance material such as carbon: a starting voltage of the lamp when the ?lamen contact of material having a resistance low rel tary electrode is cold; _ v I ' ative to the resistance of carbon; 9, bimetallic 3. In an electric gaseous discharge lamp circuit strip electrically contacting said contact of high having a ballast impedance in series with a two resistance material when said resistor is unen ?lament discharge lamp: a resistor connecting ergized and in a position to be distorted by the one end of one ?lament to one end of the other heat developed in said contact of high resistance ?lament, said resistor having an impedance large material when the latter passes current, and to compared with the ballast impedance; a bime said contact when distorted suiiiciently; tallic strip in position to be distorted by heat 30 open said bimetallic strip also being so positioned as from ‘said resistor and having one end electrical to be distorted by the heat developed in said re , ly connected to one end of said resistor; a low sistor when the latter is energized and. to short resistance contact connected to the other end of circuit said resistor by making contact with the said resistor and near but out of contact. with contact or material having a low resistance, when the other end of the bimetallic strip when said resistor is unenergized; and a second contact closed to said other end 01 said bimetallic strip when said resistor is unenergized, said second distorted su?iciently. - HENRY J. McCARTHY.