US833207A - Transformer. - Google Patents

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US833207A
US833207A US28276205A US1905282762A US833207A US 833207 A US833207 A US 833207A US 28276205 A US28276205 A US 28276205A US 1905282762 A US1905282762 A US 1905282762A US 833207 A US833207 A US 833207A
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transformer
fluid
points
sparking
potential
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US28276205A
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John J Frank
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General Electric Co
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General Electric Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01TSPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T4/00Overvoltage arresters using spark gaps
    • H01T4/08Overvoltage arresters using spark gaps structurally associated with protected apparatus
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/04Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers

Definitions

  • sparking points I arrange at or about the lowest level to which the bath may fallwithoutendangering the ap aratus;
  • current transformer-I may connect the spar oints to terminals of one or more of the For instance, when an alternatr win ings of the transformer, in which case when the fluid-level oints are no longer separated by the norma 7 5 insulation the current normally througlh 1 the 'transformei' wi rouglra circuit in shunt to the transincluding between them.
  • Fig. 2 is a trating sectional plan a detail of construction.
  • Fig. 3 1s a on the line 3 3 of Figure sectional elevation illus Fig.1.
  • tank comprising a and to ,or cover 4.
  • the tank comprises a core 1 represents an 5 arts broken away and in sec ormer embodying my inventhe windings of the transformer.
  • the windings of the transformer comprise a low-voltage coil 6 on each leg of the core and a air of l1igh-voltage coils 7 and S on one leg or the core and a pair of high-voltage coils 9 andlO on the other leg of the core.
  • the core and its windings are, supported by members which engage the tank and may be in the form of wooden bars 11.
  • the high-voltage terminals of the transformer comprise conducting-rods 12 and 13, brought out through the cover of the case throng bushings, or tubular insulators 14, which may be similar to those shown in my Patent No. 792,016, granted June 13, 1905.
  • extensions 24 are of some suitable insulating material possessing considerable mechanical strength.
  • the vertical conductin rods are each provided with a collar or enlargement 25, which engages the upper end of its upper supporting-insulator '16 or 17.
  • a nut 26, which may be of suitable insulating material, is threaded on the lower end of each extension 24. Each nut engages the lower ends of the appropriate lower insulators 16 or 17. It will thus be observed that each member comprising a conducting rod or section and a section of insulating material is secured in place and supported by a pair of upper and lower insulators 16 or 17.
  • brackets 27 The upperends of the vertical conductingrods are threaded and carry threaded brackets 27. These brackets, which can be adjusted both an ularly and longitudinally with respect to the vertical conducting-rods supporting them by reason of their threaded arrangement, maybe locked in any desired position with respect to the rods by locknuts 28.
  • Each bracket 27 is provided with a horizontally-extending arm formed with a threaded socket in which is screwed or threaded one end of a connecting-rod, the other end of which terminates in a ball sparking point or electrode. It will'thusbe observed that the vertical conducting-rods 18, 19, 20, 21, 22, and 23 are electrically connected to the sparking points or electrodes 20, 30, 31, l 32, 33, and 34, respectively.
  • the lower end has threaded u on it an arm 35, provided with a threaded socket in which is screwed the end of a rod
  • a sparking ball 38 is supported in an arm 37, similarly secured to the conducting-rod 13.
  • the terminals of the high-potential Windi gs 7, 8, 9, and of the transformer arcintended to be connected to the vertical conducting-rods 18, 19, 20,21, 22, and 23 and the terminal conductors 12 and 1.3 in variousways, depending upon the conditions under which the transformer is to operate, and the rods 18, 19, 20, 21,- 22, and 23 may be interconnected in various ways.
  • Fig. 4 the windings 7, 8, 9, and 10 are shown all in series.
  • the sparking points 36-and 29 are in shunt to the Wind-
  • sparking points 34 and 38 are in shunt to the winding 10.
  • the windings 7 and 8 are in multiple with each other and in series with the windings 9 and 10, which in turn are'm multiple with each other.
  • the Windings 7 and 8 are each protected by the sparking points 36 and 29 and also by the sparking points 32 and 20.
  • the w1ndings 9 and 10 are each protected by the sparking points 33 and 31 and by the sparking;-
  • the Windi s 7, 8, 9, and 10 are all connected in multipling pair of sparking points serve to protect each and every one of the windings.
  • the coils are all in multiple 0 crating sparking points might be elinnnateifwith safety, but inasmuch as the windings 7, 8, 9, and 10 of a particular transformer are intended to be e and each cooperatconnected at various times in the forms' shown in Diagrams .4, 5, and 6 it is preferable to provide the plurality of sparking points shown, though with the conneciinns shown in Fig. 4 one pair and with the connections shown in. Fig.
  • the normal level of the oil-bath in the casssaeov mg is indicated by the'line A A.
  • the sparking points When the artly expose the sparking points, current will-pass 1n shunt to the windings through circuits including the s arkin. points and arcs betweenthern. T is will protect the windings by diverting the current from them, and will indicate to the attendant by the disturbance produced in the voltage of the external circuits that the'transtormer needs attention.
  • a body of insulating fluid-a winding immersed therein means'for creating a difference of potential between different portions of said winding, and means automatically responsive to a change in said di'iier ence of potential when the level of the fluid falls to a predetermined stage.
  • a body ofliquid of vari able level and means for indicating a variation in said level comprisin a pair of sparking points or conductors adapted to be immersed in said liquid at one stage or level and ex osed at another stage or level, and means or creating adifference of potential between said electrodes reat enough to cause a dischar e at one 0? said stages, but not great enoug to cause a discharge at the other of said stages.
  • body of insulating fluid contained t erein, a
  • a transformer a core, windings thereon, insulators supported at opposite ends of said core, and a member supported by-said insulators, said member comprising a portion of. conducting material, another portion of insulating material, one of said portions entgaging one insulator and the other of sai portions engaging the other of said insulators, and a s arkmg point or electrode carried by and conductingsection, and a connection between said section and said winding.
  • an oil-cooled transformer a case, a body of oil contained therein, a core and hi h and low potential windings thereon normal y submerged in said oil, said highotential Winding being formed in sections a apted to be connected in various relations with each other, and a pair of cooperating electrodes or sparking points connected in shunt to each ing flui but becoming exposed upon j a predetermined fall in level of said fluid, and 1 section, said. electrodes being normally submerged in the oil but becoming exposed upon a predetermined fall in the level of the oil, each cooperating pair of electrodes being separated by a distance such that when submerged the normal difference of potential existing between them will not cause a discharge, but when exposed such difference of potential will cause a discharge.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Housings And Mounting Of Transformers (AREA)

Description

No. 833,205. PATENTED OCT, 16, 1906.
' J. J. FRANK.
TRANSFORMER.
APPLICATION FILED OCT. 14; 1905.
2 SHEETSSHEET 1 FIG].
Witnesses? Fiefi. lnvenbor, Jshn. J. Framm. W AQMW PATENTED OCT. 16, 1906.
J. J. FRANK. TRANSFORMER. APPLICATION FILED 001214, 1905- 2 SHEETSSHBET Z Invent/or,
John J. Frank.
JOHN L1. FRANK, or
STA ES,
,SCHENEUTADY,
ELECTRIC COMPANY, A CORPOR 'rsaussonmsn.
i 1 at. 33,207. "Specification of Letters Patent.
I Appligation filed October 14,1905. smunmazna'z.
To all whom it may concern:
Be it known that I, John J. FRANK, a citizen of the'Unii d States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and use Improvements in Transformers, of which the following is aspecification.
Itis a common practice at the present time to operate electrical apparatus'such as parts after the joints or fittings of insulating properties, a fall in serve not only to points or alternating-current transformers, condensers, &c.-- with the apparatus immersed in a bath of insulating fluid, such as oil. Such a bath from the ap aratus-heat enerated in it during operation, but may e relied upon to increase the effective insulation between parts subjected to diffe ences of potential. When, as is usually the case with apparatus such as transformers operated at relatively high voltages,
the like is relied upon for its the level of the bath sometimes results in serious injury-to the apparatus immersed in it, since different parts of the apparatus rising above the suriace' of the bath are no longer effectually insulated. Even if the insulation between the exposed parts is still. great enough to withstand the difference of otential between the the oil-love has fallen, the a pabe injured by such fall oi evel rise in temperature of the the bath of oil or ratus may through anundue exposed portions rect-ly cooled by contact with the bath. The fall in level may result from various causes, such as evaporation of the fluid or leaks in the tank or race tacle I'The interior -o such apparatus is ordinarily/1 from its very nature not subject to frequent inspections. it may happen, and frequently does in practice, that containing the fluid.
the level of the fluid slowly decreases to a dangerous extent without the knowledge of the attendants responsible for its care.
In'order to guard against the evil conseqlilzences resulting from a fall in the leveloi t e bath, I have provided protective devices he the apparatus. which automatically come into operation when the level of the loath approaches the danger limit, and ordinarily protect the apparatus against destruction, ut by their operation form a means for indicating the condition of the fluid-level! I have advantageously used electrodes as such protects which are no longer d1- safety. of the points to a suita insu points when 1 NEW YORK, ASSIGNOR TO'GENERAL ATIQN ()FNEW YORK.
Patented Oct. 1c, 1906.
ive devices. These sparking points I arrange at or about the lowest level to which the bath may fallwithoutendangering the ap aratus;
I connect these 3 source of electric current,
so that the difference of potential between the s arking points produced is ordinarily cient to produce sparking between the mersed or submer ed in the fluid, but sufiicientlgo produce spar ing when the points are no fluid. the sparking points fleeting them into immersed in ing ass -t ormer w n points and the are. only serves external circuits The difference of I to protecttranstormer, but through I serves to indicate to the attendant that the transformer The. various features ofiloyelty which char 8 5 immersed in said 6 5 potential between roduced by conlonger may be circuit with the apparatus the bath. the apparatus in the bath is.
current transformer-I may connect the spar oints to terminals of one or more of the For instance, when an alternatr win ings of the transformer, in which case when the fluid-level oints are no longer separated by the norma 7 5 insulation the current normally througlh 1 the 'transformei' wi rouglra circuit in shunt to the transincluding between them.
falls so that'the sparking.
easing ding 1 then the s arkmg his not'8o the winding of the its effect upon. the
is out of order.
'acterize my invention arepointed outwith particularity in "orming a part nying drawing the claims annexed of this specification.
sun
t n For a better understandmgpf 'inyinvention, how
ever, reference may ehad'to the accompa 9o descriptive. matter, in
described my invention as applied to'a modern oil-cooled insulated transformer. Of the drawings,
elevation, with tion, of a trans tion. Fig. 2 is a trating sectional plan a detail of construction. Fig. 3 1s a on the line 3 3 of Figure sectional elevation illus Fig.1. Figs. mo
4, 5, and 6 are diagrams illustrating different arrangements of high-potential windings of the transformer and .'7 illustrates a IIlOdlfiOittlOIl.
and Fi In t e drawings,
tank comprising a and to ,or cover 4.
which is placed 111 the protective device,
1 represents thecase or body portion 2, base 3, The transformer proper,
the tank, comprises a core 1 represents an 5 arts broken away and in sec ormer embodying my inventhe windings of the transformer.
' insulators 14. In'the particular construc- 5, on the two parallel legs or which are placed The windings of the transformer comprise a low-voltage coil 6 on each leg of the core and a air of l1igh-voltage coils 7 and S on one leg or the core and a pair of high-voltage coils 9 andlO on the other leg of the core. The core and its windings are, supported by members which engage the tank and may be in the form of wooden bars 11. The high-voltage terminals of the transformer comprise conducting-rods 12 and 13, brought out through the cover of the case throng bushings, or tubular insulators 14, which may be similar to those shown in my Patent No. 792,016, granted June 13, 1905.
Brackets 15, secured to bars or at the upper and lower ends of the core, support tubular insulators 16 and 17, which may e generally similar in construction to the beams 11 tion illustrated there are six of these insulators 16 in front of the transformer, as seen in Fig. 1, and six insulators 17 directly be bind the transformer. The insulators 16 on the front side of the transformer, as seen in Fig. 1, support vertical conducting rods or bars 18, 19, and 20. Similar rods or bars 21, 22, and 23 are supported by the insulators on the other side of the transformer. To the lower end of each vertical conducting-rod is secured an extension 24 by a collar 24. The
extensions 24 are of some suitable insulating material possessing considerable mechanical strength. The vertical conductin rods are each provided with a collar or enlargement 25, which engages the upper end of its upper supporting-insulator '16 or 17. A nut 26, which may be of suitable insulating material, is threaded on the lower end of each extension 24. Each nut engages the lower ends of the appropriate lower insulators 16 or 17. It will thus be observed that each member comprising a conducting rod or section and a section of insulating material is secured in place and supported by a pair of upper and lower insulators 16 or 17.
The upperends of the vertical conductingrods are threaded and carry threaded brackets 27. These brackets, which can be adjusted both an ularly and longitudinally with respect to the vertical conducting-rods supporting them by reason of their threaded arrangement, maybe locked in any desired position with respect to the rods by locknuts 28. Each bracket 27 is provided with a horizontally-extending arm formed with a threaded socket in which is screwed or threaded one end of a connecting-rod, the other end of which terminates in a ball sparking point or electrode. It will'thusbe observed that the vertical conducting-rods 18, 19, 20, 21, 22, and 23 are electrically connected to the sparking points or electrodes 20, 30, 31, l 32, 33, and 34, respectively.
The lower end has threaded u on it an arm 35, provided with a threaded socket in which is screwed the end of a rod A sparking ball 38 is supported in an arm 37, similarly secured to the conducting-rod 13. The terminals of the high-potential Windi gs 7, 8, 9, and of the transformer arcintended to be connected to the vertical conducting-rods 18, 19, 20,21, 22, and 23 and the terminal conductors 12 and 1.3 in variousways, depending upon the conditions under which the transformer is to operate, and the rods 18, 19, 20, 21,- 22, and 23 may be interconnected in various ways.
In Fig. 4 the windings 7, 8, 9, and 10 are shown all in series. In this case the sparking points 36-and 29 are in shunt to the Wind- The sparking points 32 and are 1n shunt to the winding 8. The sparking points of the conducting-rod 12' carrying a sparking ball 36.. i
33 and 31 are in shunt to the winding 9, and
sparking points 34 and 38 are in shunt to the winding 10.
in Fig. 5 the windings 7 and 8 are in multiple with each other and in series with the windings 9 and 10, which in turn are'm multiple with each other. In this case the Windings 7 and 8 are each protected by the sparking points 36 and 29 and also by the sparking points 32 and 20. Similarly the w1ndings 9 and 10 are each protected by the sparking points 33 and 31 and by the sparking;-
points 34 and 38.
In Fig. 6 the Windi s 7, 8, 9, and 10 are all connected in multipling pair of sparking points serve to protect each and every one of the windings. Of course it will be understood that when the coils are all in multiple 0 crating sparking points might be elinnnateifwith safety, but inasmuch as the windings 7, 8, 9, and 10 of a particular transformer are intended to be e and each cooperatconnected at various times in the forms' shown in Diagrams .4, 5, and 6 it is preferable to provide the plurality of sparking points shown, though with the conneciinns shown in Fig. 4 one pair and with the connections shown in. Fig. 5 two pairs of cooperating sparking )oints would ordinarily protect the entire hig voltage winding against a fall in level of the insulating fluid. in which the transformer is immersed' 1 It will be understood that the sparking points can be ad usted to bring each cooperating pair the desired distance apart and the proper distance itb0Vv It the transformen is usually desirable to have the sparking contacts some little distance above the upper end of the transformer. One of the reasons for this is that the surface of the insulating fluid on account of vforeign matter which may be carried on it is apt to beef better conductivity for high-potential discharges than is air itself. n
The normal level of the oil-bath in the casssaeov mg is indicated by the'line A A. When the artly expose the sparking points, current will-pass 1n shunt to the windings through circuits including the s arkin. points and arcs betweenthern. T is will protect the windings by diverting the current from them, and will indicate to the attendant by the disturbance produced in the voltage of the external circuits that the'transtormer needs attention. In order to limit the current-flow in shunt to the windings when arcing Occurs between electrodes, I sometimes find it advantageous to insert a resistancein series with each air of cooperating sparking electrodes. In 1g. 7 I have illustrated such an arrangement where resistances 39 are in series with the electrodes 36 and 29.
While the form of m invention disclosed in detail has. been foun to give excellent results in practice it will be understood that many changes may be made in the form of invention d1sclosed without departing from the spirit, and that certain features of my invention may be employed without a cone s ending use of others, and I do not wish the c aims hereinafter made to be limited to the particular embodiment disclosed more than 'ns made necessary by the state of the art.
What I claim as new, anddesire to secure by Letters Patent of the United States, is 1. In combination, a case containing a bath of. insulating liquid, a winding immersed in said bath, means for creating a difierence of potential between the terminals of said winding, a pair of cooperating sparking points or electrodes connected to the terminals of said Winding and arranged below the normal surface of said, fluid and separated from each other ,by a distance such that when covered by said liquid the normal potential existing between the terminals of said winding will be insulficient to cause a discharge between the points but so that when not covered by the liquid a discharge will take place between their).
'2. In combination, a body of insulating fluid-a winding immersed therein, means'for creating a difference of potential between different portions of said winding, and means automatically responsive to a change in said di'iier ence of potential when the level of the fluid falls to a predetermined stage.
3. In combination, a body of insulating fluid, a winding immersed therein, means for creating a difference of potential between different portions of said Winding, and sparking points connected to said portions,
level of said body of fluid for diminishing said sparking points being normally immersed in said fluid an d separated from each other by a distance such that when immersed the difference of potential between them will notcause a discharge so that when not immersed in said fluid said potential difference will cause a discharge between the points.
4. In combination, a body ofliquid of vari able level, and means for indicating a variation in said level comprisin a pair of sparking points or conductors adapted to be immersed in said liquid at one stage or level and ex osed at another stage or level, and means or creating adifference of potential between said electrodes reat enough to cause a dischar e at one 0? said stages, but not great enoug to cause a discharge at the other of said stages. I
5. In combination, a body of insulating fluid, acore and a windin thereon normally submerged in said fluid, e ectrodes or sparking-points connected to different portions of said winding and normally submerged in said fluid, but becoming exposed upon a predetermined fall in the level of said fluid, and means for adjusting the distance between said electrodes.
6. Ina transformer, acase or rece tacle, a
body of insulating fluid contained t erein, a
core and awindm thereon normal] submerged in said fluid, andsparking P0111138 or electrodes electricall connecte to said windin so that a di erence of potential be-' tween t em exists, said electrodes being normz'illly submer ed below the surface .of' the insu at being'separated b a'distance such that when submerged said ifl erence of 'otential will not cause a sparlcln discharge etween them while when expose it will. a
7 Inv a transformer, a core, windings thereon, insulators supported at opposite ends of said core, and a member supported by-said insulators, said member comprising a portion of. conducting material, another portion of insulating material, one of said portions entgaging one insulator and the other of sai portions engaging the other of said insulators, and a s arkmg point or electrode carried by and conductingsection, and a connection between said section and said winding.
8. In an oil-cooled transformer, a case, a body of oil contained therein, a core and hi h and low potential windings thereon normal y submerged in said oil, said highotential Winding being formed in sections a apted to be connected in various relations with each other, and a pair of cooperating electrodes or sparking points connected in shunt to each ing flui but becoming exposed upon j a predetermined fall in level of said fluid, and 1 section, said. electrodes being normally submerged in the oil but becoming exposed upon a predetermined fall in the level of the oil, each cooperating pair of electrodes being separated by a distance such that when submerged the normal difference of potential existing between them will not cause a discharge, but when exposed such difference of potential will cause a discharge.
9. In an oil-cooled transformer, cease, a body of oil contained therein, a core and high and low potential windings thereon normally submerged in said oil, Winding being formed in sections-a apted to be connected in various relations to each other, a pair of-coperatin electrodes or sparking points connected in. shunt to each section, said electrodes or sparkingpoints being normally submerged in the oil but becoming exposed on a Yredetermi ned fall in the level of the oil, am meansfor adjusting the distance between each cooperating pair of electrodes.
said highotentiel 10. In combination, a body fluid, a, core and a windin thereon normally submerged in said fluid,
sznd winding and normelly submerged in said fluid, but becomlng. exposed upon a prede ter-mined fall in the level of said fluid, and b. resistance in series with said electrodes In witness whereof I have hereunto set my hand this 13th dayof October, 1905.
JOHN J. FRANK Witnesses:
' BENJAMIN B. HULL, JOHN E. HUBBELL. v
of insulating e ectrodes or spark' 111g points connected to different portions of
US28276205A 1905-10-14 1905-10-14 Transformer. Expired - Lifetime US833207A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2717338A (en) * 1954-04-29 1955-09-06 Gen Electric Molded reactor
US2719366A (en) * 1944-10-12 1955-10-04 Otto H Schmitt Bomb simulator
US2825011A (en) * 1953-06-29 1958-02-25 Dings Magnetic Separator Co Electrically energized lifting magnet
US3910118A (en) * 1972-02-02 1975-10-07 Gerdts Gustav F Kg Probe for controlling the level of electrically conductive liquids
US5184270A (en) * 1990-06-13 1993-02-02 Abb Power T&D Company, Inc. Internal arc gap for secondary side surge protection and dissipation of a generated arc

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719366A (en) * 1944-10-12 1955-10-04 Otto H Schmitt Bomb simulator
US2825011A (en) * 1953-06-29 1958-02-25 Dings Magnetic Separator Co Electrically energized lifting magnet
US2717338A (en) * 1954-04-29 1955-09-06 Gen Electric Molded reactor
US3910118A (en) * 1972-02-02 1975-10-07 Gerdts Gustav F Kg Probe for controlling the level of electrically conductive liquids
US5184270A (en) * 1990-06-13 1993-02-02 Abb Power T&D Company, Inc. Internal arc gap for secondary side surge protection and dissipation of a generated arc

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