US2490952A - Combined lightning arrester and fuse construction - Google Patents

Combined lightning arrester and fuse construction Download PDF

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US2490952A
US2490952A US669256A US66925646A US2490952A US 2490952 A US2490952 A US 2490952A US 669256 A US669256 A US 669256A US 66925646 A US66925646 A US 66925646A US 2490952 A US2490952 A US 2490952A
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fuse
lightning arrester
terminal
tube
construction
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US669256A
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Ralph H Earle
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Line Material Co
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Line Material 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
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H85/00Protective devices in which the current flows through a part of fusible material and this current is interrupted by displacement of the fusible material when this current becomes excessive
    • H01H85/02Details
    • H01H85/44Structural association with a spark-gap arrester

Definitions

  • This invention relates to a combined lightning arrester and fuse construction.
  • Objects of this invention are to provide a combined lightning arrester and fuse construction in which the insulating barrel or tube of the lightning arrester is used for two purposes, one of which is to house the arrester itself, namely the spark gaps and the valve material, and the other to support the fuse construction thereby avoiding the expense of providing a separate and distinct support for the fuse.
  • Figure 1 is a vertical elevation of a combined lightning arrester and fuse showing one form of i the invention with parts of th lightning arrester broken away and in section.
  • Figure 2 is a similar view showing a further form of the invention.
  • the lightning arrester is indicated generally by the reference character I and the fus construction by the reference character 2.
  • the lightning arrester comprises an elongated tube 3 of porcelain, glass or other suitable insulating material. It is preferably provided with a series of spaced ribs 5 in accordance with the usual practice and is closed at its upper end except for a small aperture Ii. Valve material I, such as silicon carbide, fills the major portion of the cylinder and may extend down to the dotted line 8, for instance.
  • the lower end of the lightning arrester is provided with a series of spark gaps 9 terminating in a lower fitting or member III. This lower member is hollow and forms a socket .for a conducting rod II.
  • the conducting rod ii is formed integral with an enlarged bolt-like bottom portion I2 which is adapted to receive a nut 12.
  • the housing 3 of the lightning arrester is shouldered as indicated at I! and a brass or other metal plate [3 is welded, brazed, or otherwise secured to the rod ll. Between the shoulder l2 and the metal plate I! it is preferable to provide a gasket M.
  • Insulating cement l5 fills the enlarged lower end of the arrester and interlocks with th tube 3 as the tube is provided with a plurality of annular grooves It in accordance with the usual 2 practice.
  • A'lowenhanger ll formed of metal is held to the lower portion of the arrester by means of the nut l2. This hanger is attached to a pole or other suitable support and is grounded as indicated.
  • the upper end of the arrester is provided with an ,upper contact member II in contact with the upper portion of the valve material I.
  • a metal cap it having downwardly extending flanges overlaps thereduced upper end 20 of the arrester and is provided with an externally threaded pin 2
  • the cap I! forms in reality an upper terminal and may have a projecting portion 22 adapted to receive a clamp or other type of fastener 23.
  • the upper terminal is integral with an upper terminal arm 24, which forms the upper terminal of the fuse structure.
  • the lower terminal of the fuse structure is positioned and takes the form of an annular clamp 25 to which a pair of spring arms 28 are secured.
  • These spring arms are each provided with a loop 21 to increase their resiliency, and terminate in an outer lower terminal 28.
  • a fuse link indicated generally at 28 is removably positioned between the upper terstruction of the fuse link and of the upper and lower terminals 24 and 28 and of the spring arms 26 may be like that shown in the patent to Schultz et al., No. 2,311,092 of February 16, 1943, for Repeating cutout construction.
  • vIt is to be understood, of course, that in the present invention a single fuse link and an upper and lower terminal assembly is employed.
  • the upper terminal 24 and the lower terminal 28 are hook-like members that removably receive the upper and lower terminals 20 and ii of the fuse link, suitable eyelets 32 being provided at the upper and lower terminals. All of this construction is described in considerable detail in the above noted patent.
  • the upper terminal of the combined fuse construction and lightning arrester is connected with the high tension line 33 and the lower terminal 25 of the fuse construction is connected to the load line as indicated at 34.
  • the lower terminal of the lightning arrester' is the metal bracket I! which is grounded.
  • a hanger may be used to encircle a portion of the tube 3 of the lightning arrester and maybe attached to a pole or other support in the usual manner. Such a hanger is illustrated in Figure 2 hereinafter described.
  • the insulating tube 3 of the lightning arrester provides a very firm and adequate support for the fuse construction which latter'in no way interferes with the correct operation of the lightning arrester. Similarly, the lightning arrester does not interfere with the correct action of th fuse.
  • This form of the invention is free from radio disturbance as it will be seen that the terminal I9, 24 of the fuse construction and lightning arrester and the lower terminal 25 of the fuse construction are at line potential, and the lower terminal 25 of the fuse construction is adjacent the valve material, all of which valve material is at line potential. Thus, there is no radio disturbance produced by this construction.
  • pin II and socket-or fitting It at the lower end of the, lightning arrester provide ease in assembly and form a means of connecting the lower terminal ll with the lowest member of the spark gap assembly.
  • a spring 35 is positioned around the pin II and below the fitting lliand holds the spark gap assembly 9 upwardly in contact with the valve material.
  • the form'of the invention shown in Figure 2 is verymuch like that described in connection with Figure 1 except that the position of the spark gap and valve material is reversed.
  • the valve material is indicated by the reference character 36 in Figure 2 and the spark gap assembly by the reference character 31.
  • the fuse assembly is substantially as hereinbefore described and is indicated generally by the reference character Its lower terminal 39 is clamped about the 38. tube 40 of the lightning arrester in exactly the same manner as previously described.
  • the lower end of the lightning arrester shown in Figure 2 may be provided with a downwardly projecting annular flange 4
  • a suitable gasket being positioned between the contact member 44 and the transverse web 45 of the tube 40.
  • the upper end of the tube 40 is closed by a metal cap 45 which is spun over the beaded upper end 41 of the tube 40 in the usual manner, a suitable gasket, not shown, being provided.
  • a second rib or bead 48 is positioned below the bead 41 and a circular clamping metal member 49 encircles the tube 40 between the beads 47 and 48 and carries the terminal 50 of the fuse construction, a suitable metal jumper being bolted at its lower end to the terminal 50 and soldered, brazed, or otherwise secured to the metal cap 46.
  • the metal cap 48 is connected to the high tension line 52 in any suitable way and the lower terminal 39 of the fuse construction is connected to the load line 53 in any suitable manner.
  • the lower metal plate 42 or lower terminal of the lightning arrester is provided with a connector 54 of any suitable type, which is connected to the ground as indicated.
  • Any suitable supporting means may be provided, such as the circular clamping hanger 55 which is adapted to be attached to any support.
  • fuse assembly is eminently suitable as it is of light weight and as it throws the lower end of the fuse link downwardly away from the high tension line when rupture occurs.
  • This invention is primarily concerned with the unitary assembly of a lightning arrester and a fuse in which advantage is taken of the excellent insulation afforded by the elongated insulating tube of the lightning arrester to directly support a fuse assembly and to provide ample insulation not only between the terminals of the fuse assembly but also between the supporting means, such as the hanger and the other terminals of the assembly.
  • the fuse link assembly does not span the entire length of the elongated insulating tube but, instead, spans only a part thereof.
  • a combined fuse construction and lightning arrester comprising an elongated insulating tube having an upper terminal adapted to be connected to a line and a bottom terminal adapted to be connected to the ground and having an intermediate terminal, valve material located within said tube and extending from the'upper terminal to a point below the intermediate terminal, 'sparkgap means connected to the lower portion encircling an intermediate part of said tube and having a resilient outwardly extending portion terminating in fuse link engaging means, a fuse link between said fuse link engaging means,
  • a bottom terminal adapted to be connected to the ground, and valve material and a spark gap assembly connected in series between the upper terminal assembly and the bottom terminal and located within said tube with the valve material extending downwardly from the upper terminal to a point below the intermediate terminal, said fuse link being spaced from said spark gap as- ,sembly longitudinally of said elongated insulating tube.
  • a combined fuse construction and lightning arrester comprising an elongated insulating tube
  • a rigid upper terminal assembly carried by the upper end of said tube and adapted to be connected to a line and having fuse link engaging means
  • an intermediate load terminal having a portion encircling an intermediate part of said tube and having a resilient outwardly extending portion terminating in fuse link engaging means, a fuse link between said fuse link engaging means, a bottom terminal adapted to be connected to the ground, valve material and a spark gap assembly connected in series between the upper terminal assembly and the bottom terminal and located within said tube with the valve material extending downwardly from the upper terminal to a point below the intermediate terminal, said fuse link being spaced from said spark gap assembly longitudinally of said elongated insulating tube, said spark gap assembly having a slidable connection with said lower terminal, and spring means urging said spark gap assembly upwardly to maintain contact with said valve material.

Description

Dec. 13, 1949 H, EARLE 2,490,952
COIBINED LIGHTNING ARRBSTER AND FUSE CONSTRUCTION Filed lay 13, 1946 2 Sheets-Shoat 1 Z/M: 2?. v 32 3 0 6 F 1 2 I I a I I i I Z I l I I I I I I I v I J5 I 28 I I 21 l i I I. 32
' I I l I I I l l I s I l l l L I "'1 I I/ i 3 I 8 i I l I I I I l 5 5 9 K 35 I I4 Is" I I I5 mvzwmn |7 I2. RALPH H. EARLE.
BY g a; m
ATfOR/VEX R. H. EARLE colsnlm Lma'rume mss'rna AND FUSE- cons'rnuc'rrou Filed lay 13, 1946 2 Sheets-Sheet 2 Jul 0min. RALPH H. EARLE AT ORNEV.
Patented Dec. 13, 1949 COMBINED LIGHTNING ARRES'I'ER AND FUSE CONSTRUCTION Ralph H. Earle, Wauwatosa, Win, uaignor to Line Material Company, Milwaukee, Win, a corporation of Delaware Application May 13, 1948, Serial No. 669,256
3Claims. 1
This invention relates to a combined lightning arrester and fuse construction.
Objects of this invention are to provide a combined lightning arrester and fuse construction in which the insulating barrel or tube of the lightning arrester is used for two purposes, one of which is to house the arrester itself, namely the spark gaps and the valve material, and the other to support the fuse construction thereby avoiding the expense of providing a separate and distinct support for the fuse.
, Further objects are to provide a combined fuse and lightning arrester in which the fuse is carried on the outside of the lightning arrester to render the fuse readily accessible for refusing or inspection and in one form of the invention to so 'correlate the fuse and lightning arrester construction that there will be no radio interference.
Embodiments of the invention are shown in the accompanying drawings, in which:
Figure 1 is a vertical elevation of a combined lightning arrester and fuse showing one form of i the invention with parts of th lightning arrester broken away and in section.
Figure 2 is a similar view showing a further form of the invention.
Referring to Figure 1 it will be seen that'the lightning arrester is indicated generally by the reference character I and the fus construction by the reference character 2. The lightning arrester comprises an elongated tube 3 of porcelain, glass or other suitable insulating material. It is preferably provided with a series of spaced ribs 5 in accordance with the usual practice and is closed at its upper end except for a small aperture Ii. Valve material I, such as silicon carbide, fills the major portion of the cylinder and may extend down to the dotted line 8, for instance. The lower end of the lightning arrester is provided with a series of spark gaps 9 terminating in a lower fitting or member III. This lower member is hollow and forms a socket .for a conducting rod II. The conducting rod ii is formed integral with an enlarged bolt-like bottom portion I2 which is adapted to receive a nut 12. The housing 3 of the lightning arrester is shouldered as indicated at I! and a brass or other metal plate [3 is welded, brazed, or otherwise secured to the rod ll. Between the shoulder l2 and the metal plate I! it is preferable to provide a gasket M. Insulating cement l5 fills the enlarged lower end of the arrester and interlocks with th tube 3 as the tube is provided with a plurality of annular grooves It in accordance with the usual 2 practice. A'lowenhanger ll formed of metal is held to the lower portion of the arrester by means of the nut l2. This hanger is attached to a pole or other suitable support and is grounded as indicated.
The upper end of the arrester is provided with an ,upper contact member II in contact with the upper portion of the valve material I. A metal cap it having downwardly extending flanges overlaps thereduced upper end 20 of the arrester and is provided with an externally threaded pin 2| that extends through the opening 6 in the tube 3 and is screwed into the contact member l8, gaskets being positioned above the contact member ll and below the cap I! so as to insure sealing.
The cap I! forms in reality an upper terminal and may have a projecting portion 22 adapted to receive a clamp or other type of fastener 23. The upper terminal is integral with an upper terminal arm 24, which forms the upper terminal of the fuse structure. At a point intermediate the ends of the tube 3, the lower terminal of the fuse structure is positioned and takes the form of an annular clamp 25 to which a pair of spring arms 28 are secured. These spring arms are each provided with a loop 21 to increase their resiliency, and terminate in an outer lower terminal 28. A fuse link indicated generally at 28 is removably positioned between the upper terstruction of the fuse link and of the upper and lower terminals 24 and 28 and of the spring arms 26 may be like that shown in the patent to Schultz et al., No. 2,311,092 of February 16, 1943, for Repeating cutout construction.
vIt is to be understood, of course, that in the present invention a single fuse link and an upper and lower terminal assembly is employed. As shown in the patent, the upper terminal 24 and the lower terminal 28 are hook-like members that removably receive the upper and lower terminals 20 and ii of the fuse link, suitable eyelets 32 being provided at the upper and lower terminals. All of this construction is described in considerable detail in the above noted patent.
The upper terminal of the combined fuse construction and lightning arrester is connected with the high tension line 33 and the lower terminal 25 of the fuse construction is connected to the load line as indicated at 34. The lower terminal of the lightning arrester'is the metal bracket I! which is grounded.
It is to be noted that other means may be provided for supporting the combined lightning ar- I rester and fuse construction; For instance. a hanger may be used to encircle a portion of the tube 3 of the lightning arrester and maybe attached to a pole or other support in the usual manner. Such a hanger is illustrated in Figure 2 hereinafter described.
It is to be noted that'the insulating tube 3 of the lightning arrester provides a very firm and adequate support for the fuse construction which latter'in no way interferes with the correct operation of the lightning arrester. Similarly, the lightning arrester does not interfere with the correct action of th fuse.
When an overload occurs, the fuse link is ruptured and the lower terminal 28, which is spring urged downwardly by the resilient arms 26, quickly separates any remaining portion of the fuse link and throws the lower portion of the fuse link downwardly away from the apparatus.
This form of the invention is free from radio disturbance as it will be seen that the terminal I9, 24 of the fuse construction and lightning arrester and the lower terminal 25 of the fuse construction are at line potential, and the lower terminal 25 of the fuse construction is adjacent the valve material, all of which valve material is at line potential. Thus, there is no radio disturbance produced by this construction.
It is to be noted that the pin II and socket-or fitting It at the lower end of the, lightning arrester provide ease in assembly and form a means of connecting the lower terminal ll with the lowest member of the spark gap assembly. A spring 35 is positioned around the pin II and below the fitting lliand holds the spark gap assembly 9 upwardly in contact with the valve material. v
The form'of the invention shown in Figure 2 is verymuch like that described in connection with Figure 1 except that the position of the spark gap and valve material is reversed. The valve material is indicated by the reference character 36 in Figure 2 and the spark gap assembly by the reference character 31. The fuse assembly is substantially as hereinbefore described and is indicated generally by the reference character Its lower terminal 39 is clamped about the 38. tube 40 of the lightning arrester in exactly the same manner as previously described. The lower end of the lightning arrester shown in Figure 2 may be provided with a downwardly projecting annular flange 4| which contacts with a sealing metal plate 42. If desired, a gasket may bepositioned between the plate 42 and the flange 4!. This metal plate is welded, brazed. or otherwise secured to a pin 43 whose upper end is threaded and is screwed into the contact member 44 which engages the lower portion of the valve material, a suitable gasket being positioned between the contact member 44 and the transverse web 45 of the tube 40. The upper end of the tube 40 is closed by a metal cap 45 which is spun over the beaded upper end 41 of the tube 40 in the usual manner, a suitable gasket, not shown, being provided.
A second rib or bead 48 is positioned below the bead 41 and a circular clamping metal member 49 encircles the tube 40 between the beads 47 and 48 and carries the terminal 50 of the fuse construction, a suitable metal jumper being bolted at its lower end to the terminal 50 and soldered, brazed, or otherwise secured to the metal cap 46. The metal cap 48 is connected to the high tension line 52 in any suitable way and the lower terminal 39 of the fuse construction is connected to the load line 53 in any suitable manner. The lower metal plate 42 or lower terminal of the lightning arrester is provided with a connector 54 of any suitable type, which is connected to the ground as indicated.
Any suitable supporting means may be provided, such as the circular clamping hanger 55 which is adapted to be attached to any support.
It is to be understood that other types of fuse constructions could be employed if desired without departing from the spirit of this invention- However, the type of fuse assembly disclosed is eminently suitable as it is of light weight and as it throws the lower end of the fuse link downwardly away from the high tension line when rupture occurs. This invention is primarily concerned with the unitary assembly of a lightning arrester and a fuse in which advantage is taken of the excellent insulation afforded by the elongated insulating tube of the lightning arrester to directly support a fuse assembly and to provide ample insulation not only between the terminals of the fuse assembly but also between the supporting means, such as the hanger and the other terminals of the assembly.
It is to be noted that the fuse link assembly does not span the entire length of the elongated insulating tube but, instead, spans only a part thereof.
Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.
I claim.
1. A combined fuse construction and lightning arrester comprising an elongated insulating tube having an upper terminal adapted to be connected to a line and a bottom terminal adapted to be connected to the ground and having an intermediate terminal, valve material located within said tube and extending from the'upper terminal to a point below the intermediate terminal, 'sparkgap means connected to the lower portion encircling an intermediate part of said tube and having a resilient outwardly extending portion terminating in fuse link engaging means, a fuse link between said fuse link engaging means,
a bottom terminal adapted to be connected to the ground, and valve material and a spark gap assembly connected in series between the upper terminal assembly and the bottom terminal and located within said tube with the valve material extending downwardly from the upper terminal to a point below the intermediate terminal, said fuse link being spaced from said spark gap as- ,sembly longitudinally of said elongated insulating tube.
3. A combined fuse construction and lightning arrester comprising an elongated insulating tube,
a rigid upper terminal assembly carried by the upper end of said tube and adapted to be connected to a line and having fuse link engaging means,
an intermediate load terminal having a portion encircling an intermediate part of said tube and having a resilient outwardly extending portion terminating in fuse link engaging means, a fuse link between said fuse link engaging means, a bottom terminal adapted to be connected to the ground, valve material and a spark gap assembly connected in series between the upper terminal assembly and the bottom terminal and located within said tube with the valve material extending downwardly from the upper terminal to a point below the intermediate terminal, said fuse link being spaced from said spark gap assembly longitudinally of said elongated insulating tube, said spark gap assembly having a slidable connection with said lower terminal, and spring means urging said spark gap assembly upwardly to maintain contact with said valve material.
RALPH H. EARLE.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS 10 Number Name Date 1,159,205 Frank Nov. 2, 1915 1,873,499 Steinmayer Aug. 23, 1932 1,939,371 Spurgeon Dec. 12, 1933 2,185,105 Hill Dec. 26, 1939 15 2,376,996 Fox May 29, 1945
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2866135A (en) * 1954-12-15 1958-12-23 Mc Graw Edison Co Lightning arresters
US2971132A (en) * 1958-06-30 1961-02-07 Mc Graw Edison Co Lightning arrester constructions
US4540968A (en) * 1983-05-07 1985-09-10 Ngk Insulators, Ltd. Open fuse cutout

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1159205A (en) * 1914-05-15 1915-11-02 Gen Electric Protective device.
US1873499A (en) * 1928-07-05 1932-08-23 Line Material Co Lightning arrester
US1939371A (en) * 1930-10-27 1933-12-12 Samuel J Spurgeon Electrical protective apparatus
US2185105A (en) * 1932-08-15 1939-12-26 Allis Chalmers Mfg Co Electrical apparatus
US2376996A (en) * 1942-01-30 1945-05-29 Kearney James R Corp Electrical cutout

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1159205A (en) * 1914-05-15 1915-11-02 Gen Electric Protective device.
US1873499A (en) * 1928-07-05 1932-08-23 Line Material Co Lightning arrester
US1939371A (en) * 1930-10-27 1933-12-12 Samuel J Spurgeon Electrical protective apparatus
US2185105A (en) * 1932-08-15 1939-12-26 Allis Chalmers Mfg Co Electrical apparatus
US2376996A (en) * 1942-01-30 1945-05-29 Kearney James R Corp Electrical cutout

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2866135A (en) * 1954-12-15 1958-12-23 Mc Graw Edison Co Lightning arresters
US2971132A (en) * 1958-06-30 1961-02-07 Mc Graw Edison Co Lightning arrester constructions
US4540968A (en) * 1983-05-07 1985-09-10 Ngk Insulators, Ltd. Open fuse cutout

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