US1316095A - illingworth - Google Patents
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- Publication number
- US1316095A US1316095A US1316095DA US1316095A US 1316095 A US1316095 A US 1316095A US 1316095D A US1316095D A US 1316095DA US 1316095 A US1316095 A US 1316095A
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- US
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- Prior art keywords
- mercury
- column
- well
- passage
- contacts
- Prior art date
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- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 96
- 229910052753 mercury Inorganic materials 0.000 description 94
- 239000000969 carrier Substances 0.000 description 50
- 239000000463 material Substances 0.000 description 8
- 238000000926 separation method Methods 0.000 description 6
- 238000006073 displacement reaction Methods 0.000 description 4
- 229910052573 porcelain Inorganic materials 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 210000004907 Glands Anatomy 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000000875 corresponding Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006011 modification reaction Methods 0.000 description 2
- 230000036633 rest Effects 0.000 description 2
- 230000000717 retained Effects 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H87/00—Protective devices in which a current flowing through a liquid or solid is interrupted by the evaporation of the liquid or by the melting and evaporation of the solid when the current becomes excessive, the circuit continuity being reestablished on cooling
Definitions
- This invention relates to an electrical cutout and has for its chief object to produce an' appliance which will ⁇ be simple and more efficient than the ordinary cut-out, Eor 'fuse and be free from their objections.
- the upper end of the column is arranged in open communication with the atmosphere and a well so placed or arranged that immediately the column parts the whole of the mercury above the point of separation is discharged into the well and provides a free space for the gas or vapor generated by the parting of the column to escape to the atmosphere.
- the column is made larger in cross sectional constructing the appliance that the elec- ⁇ trical connection can instantly be restored ⁇ by tilting the apparatusso thatthe mercury runs from the well to the column. This may be effected by forming the aforesaid .well or pocket at one side of the upper end of the column and making itl large enough to contain moreJ mercury than is sufficient to ill the column. This well or pocket is ar- Speciiication of Letters Patent.
- auxiliary means l are employed for drawing or forcing the mercury into the carrier to make and re-make the column.
- This auxiliary means may comprise a pump which may be situated 'either at the top, or at the bottom of the carrier, and be actuated by hand, or automatically during the tilting of the carrier.
- two or more columns of mercury may be arranged in parallel and a preferred construction consists invarranging the ends of the columns to converge to a single aperture or passage at one or both ends of the carrIer.
- the passage or passages for the column or columns may be formed in an interf changeable core or in the carrier itself.v If
- an indicator may be used in connection with the appliance to show whether the circuit is broken or unbroken and such indicator may be actuated bythe aforesaid gas or by variation in the level of mercury in the well.
- Figure l is a vertical section of an electrical .cut-out operating on the principle ofl this invention and shown in hinged connection with an insulated base.
- Fig. 2 is a front elevation of the carrier shown partly in section.
- Fig. 3 shows the appliance in its resetting position.
- p Fig. 4 is a plan of the top cover.
- Fig. 5 is an inverted plan of the top cover.
- Fig. 6 is a plan of the carrier with the top cover removed.
- Fig. ⁇ 7 is a section taken approximately on line 7-7 of Fig. 1.
- Fig. 8 isa plan and Fig. 9 an inverted Fig. l0 is asection showing a pump applied to the bottom cover.
- Fig. 11 is a section of a solid top contact.
- Fig. 12 is a section and Fig. 13 an end view of a core having passages arranged in parallel.
- Fig. 14 is a diagram of a form of indicator adapted tovbe actuated by the displacement of mercury.
- A indicates the column of mercury
- B the carrier
- C the carrier
- C1 the two contacts
- D the well or pocket.
- the carrier vB may be constructed from porcelain or other appropriate material and is provided at its ends with two detachable caps 1 which make a liu'id tight joint with the body of the carrier through the intervention of packing b2. Extending through the cap b are two vent passages d which form a communication between the top of the well D and a pocket or recess d1 hereinafter referred to. rl ⁇ he body ot the carrier contains a core E which may be constructed from cement, reclay, porcelain, silica, or other suitable material. This core may constitute a permanent part of the carrier. or it may be detachable as shown, a tight joint between the carrier and core being made by packings e el.
- the cores By making the cores interchangeable a very wide range is given to the apparatus as the same can be used for currents varying from say 5 to 1000 amperes by merely substituting one core for another. Extending through the core is a passage for the column ot' mercury A, the smallest cross sectional area of such passage, determining the amount of current that will pass before causing the column to part. This portion is advantageously arranged midway between the ends of the column as shown in Fig. 1. The upper and lower ends of the passage are advantageouslv slightly countersunk to form two shallow basins e2 which become filled with mercury and afford a good ,contacting surface with the upper and lower contacts C C1.
- these contacts comprise spring pressed plirngersxslidably mounted in sockets c c1 which are attached to the covers b1 respectively.
- the nuts cX which retain the contacts C C1 in their respective sockets are preferably constructed from material possessing no aliinity for mercury.
- the spring of the lower contact is made stronger than the spring for the upper one to retain the core in position against its packing e.
- the upper contact C is cut away at c2 to form a free passage for the mercurv to and from the well D and the latter ma;r be formed with a spout or channel d2 to facilitate such passage.
- the cut away portion in the top contact is advantageously shaped as shown at 02 in Fig. 1l.
- Projecting from the sockets c c1 are contact blades c3 c'l which extend through the side of the caps, the blade c4 being detachably hinged to a contact c on an insulated base c7 and the upper blade c3 being adapted to be slid into and out of engagement with a spring contact cS on the Said base.
- a piston F works in a recess or cylinder ,t in the contact C and is normally retained in its raised position by a spring f1 which encircles the upper end of the pistou rod f2. In this arrangement the carrier is tilted to till the space above the core E with mercury and the piston is then actuated to force the mercury down the core passage until the latter is lilled.
- a plunger F 1 is mounted in the bottom contact C1 and passes through a gland f3 and stuffing box f4.
- the core E may be formed with two or more passages arranged in parallel and in the example shown in Figs. 12 and 13 the core is formed with four passages e3.
- the passages are arranged to converge to a single opening e4 ⁇ at the upper los or filling end, the lower portions of the passages being parallel.
- the convergingand parallel passages are reduced in cross sectional area towa-rd the center of the core to bring the point of highest resistance midway between the ends cf the core.
- the indicator comprises a two armed lever pivoted near one end to a light frame g having two'legs g1 connected by a cross piece g? and a third leg g3 to a oat-g
- the latter rests on the surface of the mercury in the well and when the level of the mercury rises owing to the column parting, the float, frame and lever are lifted bringing the short arm of the lever against an abutment g5 on a strap g* which forms part of an attachment for the top cover b with the result that the lever is tilted'until its long arm projects above the top of the cover b and indicatesthat the circuit is broken.
- a numl ber of carriers In the case of a distribution board, a numl ber of carriers would be separately mounted on a base or bases and take the place of the ordinary fuses and carriers. ⁇ For certain -classes of work the carrier may be armored or inclosed in a metal box.
- the circuit is broken without arcing and without any surge of current.
- the circuit is always broken by the eXact amount of current for which ythe apparatus is set with the result that its action is absolutely constant.
- the apparatus is entirely foolproof and cannot be tampered with to make it take a heavier current than it is designed for. No replacemen-ts are required and all fuse wires are done away with.
- the apparatus can be used in place of the movable contacts on the ordinar'y ⁇ doub-le pole switch by using two car- -riers linked together.
- a top contact having a curved defiecting surface, a bottom contact, a passage connecting same with the top contact, an overflow arranged in free and open communication with the deecting surface of the top contact, an air vent arranged in open communication with the passage, and a body of mercury adapted to lill the said passage and make an electrical connection between the said contacts, said deflecting surface being positioned to deilect mercury into said reservoir as it flows from said passage when a blow out takes place.
- a detachable core having a plurality of longitudinal circuit-maintaining passages communicating with a single opening.
- a detachable core having a plurality of longitudinal circuit-maintaining passages each of which is reduced in cross sectional area at some portion of its length, all of said passages communicating with a single opening.
- contact blades and hinge being such as to' cause mercury to flow from the well into the passage and reform the column when the carrier is tilted.
- a carrier provided with two contacts having laterally projecting blades, a passage communicating with the the column of mercury, a well situated at one side of the upper end of the passage and in open communication therewith, an air vent arranged in open communication with the passage, an insulated base provided with two contacts respectively arranged in hinged and sliding connection with the contact blades, the relative positions oft the well, contact blades and hinge being such as to cause mercury to flow from vthe well into the passage and reform the colv two contacts, a carrier provided with two contacts having laterally projecting blades, a passage communicating with said contacts for the column of mercury, a well situated at one side of the upper end of the passage and in open communication therewith, an air ventv arranged in open communication with the passage, an insulated base provided with two contacts respectively arranged in hinged and sliding connection with the contact blades, therelative positions of the well, contact blades and hinge being such as to cause mercury to flow from the well to
Landscapes
- Arc-Extinguishing Devices That Are Switches (AREA)
Description
W. H. ILLINGWORTH.
ELECTRICAL CUT-OUT.
APPLICATION FILED Nov. 13, |918.
'Patented Sept. 16, 1919.
2 SHEETS-SHEET l.
W. H. ILLINGWORTH.
ELECTRICAL CUT-OUT.
IAPPLICATION FILED NOV. 13, 1918.
Patented sept. 1 6, 1919 2 SHEETSSHEET 2 FGJZ.
Fia. 1,2.'
llllllll WILLIAM HENRY- ILLINGWORTH, or HALIFAX, ENGLAND.
ELECTRICAL CUT-OUT.
To all whom t1/Lay concern Be it known that I, WILLIAM HENRY ILLINGwoRTII, a subject of the King of Great I Britain, residing at l Ruskin Terrace, Lee Mount, Halifax, in the county of York, England, have invented certain new and- .useful Improvements in Electrical Cut-Outs,
of which the following is a specification.V
This invention relates to an electrical cutout and has for its chief object to produce an' appliance which will `be simple and more efficient than the ordinary cut-out, Eor 'fuse and be free from their objections.
Among these objections are arcing with its resulting injuries such as fused terminals, broken bases and the like. A sudden surge of current produced by breaking of the circuit, or blowin of the fuse owing to adead short circuit. nconstancy in the action of a cut-out or,V fuse wire and injuries or lires produced by" the substitution for the correct wire of a thicker'fuse wire, or of one having a higher fusing point.
In overcoming these objections I employ a cut-out of the kind in which a column of mercury or other liquid (hereinafter re-v ferred to as mercury) forms an electrical connection between two contacts but parts at some portion of its length when the current reaches a predetermined amperage.
v According to this invention the upper end of the column is arranged in open communication with the atmosphere and a well so placed or arranged that immediately the column parts the whole of the mercury above the point of separation is discharged into the well and provides a free space for the gas or vapor generated by the parting of the column to escape to the atmosphere.
y The column is made larger in cross sectional constructing the appliance that the elec-` trical connection can instantly be restored` by tilting the apparatusso thatthe mercury runs from the well to the column. This may be effected by forming the aforesaid .well or pocket at one side of the upper end of the column and making itl large enough to contain moreJ mercury than is sufficient to ill the column. This well or pocket is ar- Speciiication of Letters Patent.
Patented Sept. 16, 1919.
Application led November 13, 1918. Serial No. l262,399.
ranged in line with the contacts i and the lower contact blade may be pivoted to a contact or terminal on an insulated base,'the
'arrangement beingsuch that by tiltingthe carrier to disconnect the upper contact from the corresponding terminal on the insulated base, the mercury in the well, or a portion of it flows back and re-for-ms the column, thereby restablishing the electrical connection between the upper and lower contacts.
In practice it is found that a small amount of gas is generated during the parting of the column and to allowthe escape of such gas a -vent is formed in the carrier above the well. When a column of 'small diameter is employed for currents of low a'mperage, auxiliary means l are employed for drawing or forcing the mercury into the carrier to make and re-make the column. This auxiliary means may comprise a pump which may be situated 'either at the top, or at the bottom of the carrier, and be actuated by hand, or automatically during the tilting of the carrier. When a current of heavy amperage is emi ployed two or more columns of mercury may be arranged in parallel and a preferred construction consists invarranging the ends of the columns to converge to a single aperture or passage at one or both ends of the carrIer. The passage or passages for the column or columns may be formed in an interf changeable core or in the carrier itself.v If
desired an indicator may be used in connection with the appliance to show whether the circuit is broken or unbroken and such indicator may be actuated bythe aforesaid gas or by variation in the level of mercury in the well.
In the accompanying drawingsz` Figure l is a vertical section of an electrical .cut-out operating on the principle ofl this invention and shown in hinged connection with an insulated base.
Fig. 2 is a front elevation of the carrier shown partly in section. l
Fig. 3 shows the appliance in its resetting position. p Fig. 4 is a plan of the top cover.
Fig. 5 is an inverted plan of the top cover. Fig. 6 is a plan of the carrier with the top cover removed.
Fig.` 7 is a section taken approximately on line 7-7 of Fig. 1.
Fig. 8 isa plan and Fig. 9 an inverted Fig. l0 is asection showing a pump applied to the bottom cover.
Fig. 11 is a section of a solid top contact.
Fig. 12 is a section and Fig. 13 an end view of a core having passages arranged in parallel.
Fig. 14 is a diagram of a form of indicator adapted tovbe actuated by the displacement of mercury. y
A indicates the column of mercury, B the carrier, C, C1 the two contacts, D the well or pocket.
The carrier vB may be constructed from porcelain or other appropriate material and is provided at its ends with two detachable caps 1 which make a liu'id tight joint with the body of the carrier through the intervention of packing b2. Extending through the cap b are two vent passages d which form a communication between the top of the well D and a pocket or recess d1 hereinafter referred to. rl`he body ot the carrier contains a core E which may be constructed from cement, reclay, porcelain, silica, or other suitable material. This core may constitute a permanent part of the carrier. or it may be detachable as shown, a tight joint between the carrier and core being made by packings e el. By making the cores interchangeable a very wide range is given to the apparatus as the same can be used for currents varying from say 5 to 1000 amperes by merely substituting one core for another. Extending through the core is a passage for the column ot' mercury A, the smallest cross sectional area of such passage, determining the amount of current that will pass before causing the column to part. This portion is advantageously arranged midway between the ends of the column as shown in Fig. 1. The upper and lower ends of the passage are advantageouslv slightly countersunk to form two shallow basins e2 which become filled with mercury and afford a good ,contacting surface with the upper and lower contacts C C1. In the example shown these contacts comprise spring pressed plirngersxslidably mounted in sockets c c1 which are attached to the covers b1 respectively. The nuts cX which retain the contacts C C1 in their respective sockets are preferably constructed from material possessing no aliinity for mercury. The spring of the lower contact is made stronger than the spring for the upper one to retain the core in position against its packing e. The upper contact C is cut away at c2 to form a free passage for the mercurv to and from the well D and the latter ma;r be formed with a spout or channel d2 to facilitate such passage. rl`his passage is made as large as possible to prevent any choking action of the mercury when the column parts and in order that the whole of the mercury above the point of separation may be delected or thrown over into the well the cut away portion in the top contact is advantageously shaped as shown at 02 in Fig. 1l. Projecting from the sockets c c1 are contact blades c3 c'l which extend through the side of the caps, the blade c4 being detachably hinged to a contact c on an insulated base c7 and the upper blade c3 being adapted to be slid into and out of engagement with a spring contact cS on the Said base. To utilize the apparatus it is charged with mercury until the column is completely filled and the mercury overfiows a little into the well. In this condition an electrical connection is established between the upper and lower contacts by the column of mercury as soon as the top cover b is placed in position. lf a heavier current than the apparatus is designed for passes through it, it causes a portion of the mercury in the column to be discharged into the well and the column ultimately vaporizes and parts at the portion ot smallest cross sectional area with the result that the circuit is broken. lllhen this takes place a slight discharge of gas escapes by way ol? the vent passages Z Z and such gas may be used to actuate an indicator to show that the circuit is broken. To restore the electrical connection between the contacts, all that is necessary is to tilt the arrier tc the position shown in Fig. 3. so that a portion of the mercury in the well returns and refills the column and basin above the point of separa tion, the well being large enough to retain an excess quantity of mercury to provide for any shrinkage or loss which may take place during the continued working of the apparatus. lf the core passage is too small for the mercury to pass down by gravity a pump is used. In Fig. 1, a piston F works in a recess or cylinder ,t in the contact C and is normally retained in its raised position by a spring f1 which encircles the upper end of the pistou rod f2. In this arrangement the carrier is tilted to till the space above the core E with mercury and the piston is then actuated to force the mercury down the core passage until the latter is lilled.
In the modification shown in Fig. 10, a plunger F 1 is mounted in the bottom contact C1 and passes through a gland f3 and stuffing box f4. The pump parts-are constructed from any suitable material which will not possess an aliinity for mercury. lf no pump is employed. or if it is applied to the bottom contact a solid top contact such as that shown in Fig. l1, would be used. For heavy currents the core E may be formed with two or more passages arranged in parallel and in the example shown in Figs. 12 and 13 the core is formed with four passages e3. 'lo insure all the passages being completely filled when the carrier is tilted, the passages are arranged to converge to a single opening e4 `at the upper los or filling end, the lower portions of the passages being parallel. The convergingand parallel passages are reduced in cross sectional area towa-rd the center of the core to bring the point of highest resistance midway between the ends cf the core.
In Fig. 14, Gis an indicator adapted to be operated by displacement of mercury in the well D. In the example shown the indicator comprises a two armed lever pivoted near one end to a light frame g having two'legs g1 connected by a cross piece g? and a third leg g3 to a oat-g The latter rests on the surface of the mercury in the well and when the level of the mercury rises owing to the column parting, the float, frame and lever are lifted bringing the short arm of the lever against an abutment g5 on a strap g* which forms part of an attachment for the top cover b with the result that the lever is tilted'until its long arm projects above the top of the cover b and indicatesthat the circuit is broken.
In the case of a distribution board, a numl ber of carriers would be separately mounted on a base or bases and take the place of the ordinary fuses and carriers. `For certain -classes of work the carrier may be armored or inclosed in a metal box.
By the invention described 4the circuit is broken without arcing and without any surge of current. The circuit is always broken by the eXact amount of current for which ythe apparatus is set with the result that its action is absolutely constant. The apparatus is entirely foolproof and cannot be tampered with to make it take a heavier current than it is designed for. No replacemen-ts are required and all fuse wires are done away with. The apparatus can be used in place of the movable contacts on the ordinar'y` doub-le pole switch by using two car- -riers linked together.
What I claim as my invention and desire to secure by Letters Patent in the United States is :e-
l. In an electrical cut out, the combination of an upper contact cap provided with a socket, alower contact cap also provided with a socket, means engaging said Vvsockets and containing sufficient mercury to provide an electrical connection between said contacts, an `overflow to receive the mercury thrown by vaporizatlon when the connection is broken and an air vent in one of said caps for the free escape of vapor produced by the said breakage.
2. In an electrical cut out the combination of an upper contact cap provided with a socket, a lower contact cap also provided ywith a socket, a core engaging said socket and provided with a plurality of mercurycontaining passages providing mercurial columns in parallel between said contacts, an overfiow to receive a portion of the mercury overflow, and a body of mercury adapted to fill the said passage and make an electrical connection between the said contacts.
4. In an electrical cut-out, the combination of a top contact having a curved defiecting surface, a bottom contact, a passage connecting same with the top contact, an overflow arranged in free and open communication with the deecting surface of the top contact, an air vent arranged in open communication with the passage, and a body of mercury adapted to lill the said passage and make an electrical connection between the said contacts, said deflecting surface being positioned to deilect mercury into said reservoir as it flows from said passage when a blow out takes place. y
5. In an electrical cut-out, the. combination of an upper contact, a lower contact, means for establishing an electrical connection between said contacts by a column of mercury, an overflow to receive mercury predetermined portion ofits length between its ends.
7 In an electrical cut-out actuated by the breaking of a column of mercury, a detachable core having a plurality of longitudinal circuit-maintaining passages communicating with a single opening. Y
8. In an electrical cut out actuated by the breakingl of a column of mercury, a detachable core having a plurality of longitudinal circuit-maintaining passages each of which is reduced in cross sectional area at some portion of its length, all of said passages communicating with a single opening.
9. In anelectrical cut out actuated by the breaking of a column of mercury, means for pivotally supporting the cut out element at one end, and means whereby the tilting o-f said element upon its pivotal support will remake the column.
10. In an electrical cut-out actuated by the breaking of a column ofl mercury between said contacts for `and in open communication therewith, an air vent arranged 1n open communication with the well, an insulated base provided lwith two contacts respectively arranged in hinged and sliding connection with the contact blades, the relative positions ofthe well,
contact blades and hinge being such as to' cause mercury to flow from the well into the passage and reform the column when the carrier is tilted.
1l. In an electrical cut-out actuated by the breaking of a column of mercury between two contacts, a carrier provided with two contacts having laterally projecting blades, a passage communicating with the the column of mercury, a well situated at one side of the upper end of the passage and in open communication therewith, an air vent arranged in open communication with the passage, an insulated base provided with two contacts respectively arranged in hinged and sliding connection with the contact blades, the relative positions oft the well, contact blades and hinge being such as to cause mercury to flow from vthe well into the passage and reform the colv two contacts, a carrier provided with two contacts having laterally projecting blades, a passage communicating with said contacts for the column of mercury, a well situated at one side of the upper end of the passage and in open communication therewith, an air ventv arranged in open communication with the passage, an insulated base provided with two contacts respectively arranged in hinged and sliding connection with the contact blades, therelative positions of the well, contact blades and hinge being such as to cause mercury to flow from the well to a recess above the top of the passage when the carrier is tilted and means for nlechanically causing the mercury to pass through the passage and make the column.
lfn testimony whereof l atlizi my signature in presence of two witnesses.
Wllilillllli HENR' llililNGWOR' ll Witnesses: AUGUsTUs E. Insertar,
LUCY OU'ri-iwnrrn.
Publications (1)
Publication Number | Publication Date |
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US1316095A true US1316095A (en) | 1919-09-16 |
Family
ID=3383582
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US1316095D Expired - Lifetime US1316095A (en) | illingworth |
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Country | Link |
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US (1) | US1316095A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2732460A (en) * | 1953-01-29 | 1956-01-24 | R benchemoul | |
US3117203A (en) * | 1960-05-17 | 1964-01-07 | Gen Electric | Circuit protective devices and circuits |
US3753190A (en) * | 1969-06-10 | 1973-08-14 | Mitsubishi Electric Corp | Current limiting device |
-
0
- US US1316095D patent/US1316095A/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2732460A (en) * | 1953-01-29 | 1956-01-24 | R benchemoul | |
US3117203A (en) * | 1960-05-17 | 1964-01-07 | Gen Electric | Circuit protective devices and circuits |
US3753190A (en) * | 1969-06-10 | 1973-08-14 | Mitsubishi Electric Corp | Current limiting device |
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