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US903812A - Electrical protective apparatus. - Google Patents

Electrical protective apparatus. Download PDF

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Publication number
US903812A
US903812A US30492906A US1906304929A US903812A US 903812 A US903812 A US 903812A US 30492906 A US30492906 A US 30492906A US 1906304929 A US1906304929 A US 1906304929A US 903812 A US903812 A US 903812A
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Prior art keywords
spring
rods
protector
pair
plate
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US30492906A
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Frank B Cook
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Priority to US373140A priority patent/US870495A/en
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    • 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

  • My nvention relatesto protective appara-tus'coniprising protective devices for proamaguuaaa electrical circuits and appa- "ratfus thereof, such as telephone, l
  • fire alarm circur is and apparatus, rom infrom abnormally large currents of electficity from'electric light; trolley or power circuitafor the like, these currents being nerally termed sneak currents, in combi'ii'ation with protective devices adapted to 0 protect the delicate circuits and apparatus thereof from highpotential electricity such .1 as lightning.
  • the principal objects of this invention are toprovi'de simplicity of construction in apparatus of-the. character specified; to 'provide Tan arrangement of such apparatus which is very efiicient and thoroughly reliable in its operation; to provide means to permit'of resetting and resecuring the apparatus in reset operative position after operation, whereby the apparatus is tested preparatory for another operation; to provide improved means removing any portion thereof; to provide improved means for grounding certain cit-- -.-cuits when the apparatus operates, and for controlling suitable catetheoperationof the devices; and to provide improved means for holding the parts ofthe apparatus in alinement to improve Ithje serv'iceability of same.
  • Fig 3 is atop end view of Fig. 1, Fl shows in detail the spring a of Fig. 1. i ;Q pel -"Spect ive viewof the protector late with the insulating strips Specification of Letters Patent. I
  • 1 is a ground plate, preferably made of two formed pieces like parts in the are'mounted spring members 3 3, 4 4, 5 5, and 6 6, suitably'insulated from eaohother by insulation 7.
  • Springs 3 3 are preferably the line springs andare adapted to hold the lightning arresters 8' 8 in p'lace against the projections 9 9 on the ground plate which hold the pairs of lightning arresters apart.
  • Ground plate 1 may be of any desirable length to accommodate a series of pairs of the protective apparatus; The free ends of receive the thermal protector deviceslO 10, which are preferably connected to springs 3 3 by screw connection as shown.
  • the thermal protector 10 is prefer- "ably constructed with an inclosing shell electrically connected with the terminal end 11 and insulated from the screw end 12.
  • the shell of the protector 10 incloses' the heat producing means which is connected in a series circuit with the terminal end 11 and the screw 12.
  • Each sp'rin 5 is provided with a contact portion l3iadapted to engage a contact on the switchboard spring 6, to form a se arablje contact adapted to receive a test p ug for o ening the circuit between the switchboat and the line for testing.
  • This contact at 13 is preferably made of platinum so as not; to corrode.
  • The' line circuit through an'yset of the rote'ctive apparatus is from the line, throu ,line spring'3, the thermal protector 19, t '61f1'66 end of spring 5, contact portion 13, and switchboard spring 6, tothe switchboard.
  • each spring 5 is preferably connected preferably made of hard rubber, are preferably inserted through the ground plate 1 between pairs of the protective apparatus, to keep the several springs of .each set in alinement, and to separate thesprings of each pair from the springs of the adjacent pairs.
  • These insulating strips H are each provided with a shoulder 15 adapted to rest against the ground plate 1.
  • the strips 14 14, taken in a series, are alternately inserted through the plate 1 in opposite directions, as shown in Fig. 5, so that the shoulders 15 on the first, third, fifth etc. bear against the plate l'on one side thereof, and those on the second, fourth, sixth, etc. bear against the plate 1 on the opposite side thereof.
  • strips 14 14 are bound together bycontact rods 16 and 17 which extend through the series. When the strips 14 14v are thus bound together they are rigidly held in place,-due to the shoulders 15 15 on opposite sides of plate 1'.
  • One of the rods 16 or 17 may be connected in circuit with an alarm 44 and battery lf), one terminal of the battery being connected to ground in a manner well understood, and the other rod 16 or 17 may be connected direct to ground
  • contacts 18 and 19 of spring tively, independently, dueto spring 4 being split as shown.
  • An insulator 20 extends through springs 3, 4;, 5, and 6 of each set and is arranged so that the operation of springs 5 and 6 controls the operation of spring at, thereby causingcontacts 18 and 19 of spring 1 to firmly engage rods 16 and 17.
  • Spring 4 engaging rods 16 and 17 also limits the extent of the operation of springs 5 and 6. Spring 4 isnormally out of contact .with
  • Line springs 3 3 terminate in line terminals 21 22 and switchboard springs (i b terminate in switchboard terminals 23 2-1, terminals and 24 being crossed over shown, to arrange line terminals 21 and 22 together and switchboard terminals 23 and 24: together.
  • the line conductors are preferably connected to terminals 21 and confluctors leading to the central station switch board, in telephone systems or the like, are preferably connected to terminals 23 2 1.
  • Line springs '3 3 are provided with. projections :25 25 thereon to form stops for the outer carbon blocks of the lightning arresters 8 8, to correspond with the stops formed by the ground plate 1 for the inner carbon blocks of the lightning arresters.
  • the operation of the protective apparatus is as follows: When an abnormally large current traverses a thermal protector for a sufiicient length of time, this current gener--.
  • a insulatingstrips carried by the said insulating strips, tector associated with the-apparatus for operation, and a spring member arranged to engage the said rods when the protector opcrates.
  • circuit controlling 'means operable protector a plurality of conducting rods associated with the I apparatus, and a spring member for engaging the said rods upon the operation of the apparatus.
  • Protective apparatus comprising a thermal protector and a. plurality of conducting rods associated therewith, means for operating the protector u on abnormal current conditions, and a'circuit-controlling member for engaging the said rods upon the operation of the protector.
  • Apparatus of the class specified comthermal protectors a mounting plate therefor, means for suitably. operatin the protectors, a plurality of conducting ro s arranged parallel with. the said plate, and a series of spring members normally held out of contact-,with the said rods' by the said operating Imeans and each arranged to ensaid rods upon the operation of onding thermal protector.
  • An electrothermal protector comprising conducting member, a heat cartridge removably mounted" on the saidconducting member, an operable spring member, an easily fusible metallic solder normally holding thesaid spring member under tension and connecting same with the heat cartridge for purposes substantiallyas described.
  • a pair of spring membersp aheat cartridge electrically connected fro one of the spring members by a screw connection and to the and a third spring member normally con ,nected with one of the spring members of the pair by a separable contact.
  • Electrical protective apparatus comprising a'pair of conducting members and a thermal protector connected'to one said conducting member by a screw connection and to the other by a solder connection, and a third conducting member normallyelecplate, a plurality of conducting rods 'a mounting plate, a
  • thermal pro- 9 Electrical protective apparatus com prising a thermal protector electrically connected' in circuit with. a plurality of conducting members and having a screw connection between the protector and one of'the said conducting members, and another com ducting member normally electrically connected with one of the said plurality of conducting members by a separable contact.
  • a thermal protector electrically connected with one springmember by a screw connection and with the other spring member by a solder connection adapt 'ed to be opened upon the operation of the device, and a third spring member normally connected with the outer spring of the pair by a separable contact, adapted to stay closed upon the operation of the device.
  • a mounting plate conducting rods extending parallel with the said plate, a spring member carrying) spring mem er normally out of contact'with the said. rods, 'a third spring member normally soldered to the thermal protector, a fourth spring member normally in contact with the said third spring member, the said third and fourth spring members operating away from the mounting plate under ab and an insulating member coiiperating with the said spring members to cause the said second springmember to engage the said rods upon the operation of the apparatus.
  • a mounting plate tion each provided with a shoulder to bear against the said plate andalternately inserted through same in opposite directions, a pair of conducting'rods on each side of the mounting late carried by the said insulating strips, suitable protective apparatus mounted in a mounting plate, and a series of spring 111cmbers on each side of the mounting plate each arranged to enga e the corresponding pair of conducting rods upon the operation of the protective apparatus; 7 v y 13.
  • Apparatus of the class specified comprising a sprin member and a thermal protector coiiperatmg therewith, and a second spring member engaging the first at a cont-apt openable by pressing one spring member toward the other.

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Description

F. B. (300K. ELECTRICAL PRGTEGTIVB APPARATUS.
APPLIOATIOH FILED MAB. 8, 1906.
no 0 9 1L 0 1 V o N d. E w x n...
2 SHEETS-SHEET l.
witnesses @Mfi. M.
F. B; 00015.; ELEGTRIGAL PROTEGTIVTB APPARATUS.
APPLICATION FILED MAB. 8, 1906.
' Patented Nov 10, 1908..
INVEN TO 1 Zak/ w.
. Jama -17.1..
ELECTRICAL roams tithe, United States, residing atChiri zlthecounty of Cook and State of have invented new and useful-Imin'g drawings, illustrating same. My nvention relatesto protective appara-tus'coniprising protective devices for proamaguuaaa electrical circuits and appa- "ratfus thereof, such as telephone, l
fire alarm circur is and apparatus, rom infrom abnormally large currents of electficity from'electric light; trolley or power circuitafor the like, these currents being nerally termed sneak currents, in combi'ii'ation with protective devices adapted to 0 protect the delicate circuits and apparatus thereof from highpotential electricity such .1 as lightning.
' The principal objects of this invention are toprovi'de simplicity of construction in apparatus of-the. character specified; to 'provide Tan arrangement of such apparatus which is very efiicient and thoroughly reliable in its operation; to provide means to permit'of resetting and resecuring the apparatus in reset operative position after operation, whereby the apparatus is tested preparatory for another operation; to provide improved means removing any portion thereof; to provide improved means for grounding certain cit-- -.-cuits when the apparatus operates, and for controlling suitable catetheoperationof the devices; and to provide improved means for holding the parts ofthe apparatus in alinement to improve Ithje serv'iceability of same.
"In the accompanying drawings illustrat- I ing the ,preferred form of my invention, Eigure l'i-llustrates a pair of protective apparatus; mounted on opposite sides of a m nd plate, the apparatus on the right fjside being shown in a set position for operation, and the apparatus on ft; hand side beingshown in an'oper- 2 is an edge View of fission, g-
Fig 3 is atop end view of Fig. 1, Fl shows in detail the spring a of Fig. 1. i ;Q pel -"Spect ive viewof the protector late with the insulating strips Specification of Letters Patent. I
known th t I, FRANK B. Coon, a
nts in Electrical Protective Appa us, o'fewhich the following is a specifica-' reference being had to the-accompany to permit of testing the-several circuits through the apparatus without.
alarm circuits to indi- {the'alarm' circuit and'grgounding.
'. raANK B. 000K, or CHICAGO, ILLINOIS. P. RO'I.EG'1IVE arraaa'rus.
Patented m. 10, 1908.
Application am March 8, 1906. Serial No. 304,929.
rods carried thereby, showing the strips 14 inserted alternately from opposite sides of the mounting plate and the alarm circuit, .ground connection, andswitching means for the said rods.
Likeycharacters refer to several figures.
Referring to the-drawings, 1 is a ground plate, preferably made of two formed pieces like parts in the are'mounted spring members 3 3, 4 4, 5 5, and 6 6, suitably'insulated from eaohother by insulation 7. Springs 3 3 are preferably the line springs andare adapted to hold the lightning arresters 8' 8 in p'lace against the projections 9 9 on the ground plate which hold the pairs of lightning arresters apart. Ground plate 1 may be of any desirable length to accommodate a series of pairs of the protective apparatus; The free ends of receive the thermal protector deviceslO 10, which are preferably connected to springs 3 3 by screw connection as shown. When the apparatus is set for operation, the free with and soldered to the corresponding thermal protector 10, by an easily-fusible solder, as shown on the right hand side of Fig. 1. The thermal protector 10 is prefer- "ably constructed with an inclosing shell electrically connected with the terminal end 11 and insulated from the screw end 12. The shell of the protector 10 incloses' the heat producing means which is connected in a series circuit with the terminal end 11 and the screw 12. l i
The articular thermal protector herein shown orms the subject matter of my copending application for Letters Patent on electro-thermal protector, Serial No. 316,153, filed May 10, 1906. o Each sp'rin 5 is provided with a contact portion l3iadapted to engage a contact on the switchboard spring 6, to form a se arablje contact adapted to receive a test p ug for o ening the circuit between the switchboat and the line for testing. This contact at 13 is preferably made of platinum so as not; to corrode. The' line circuit through an'yset of the rote'ctive apparatus is from the line, throu ,line spring'3, the thermal protector 19, t '61f1'66 end of spring 5, contact portion 13, and switchboard spring 6, tothe switchboard.
Insulating strips 1 4 14,
of sheet metal secured together, upon which 7 groundplate 1, preferably as shown, between line springs 3 3 are preferably adapted to end of each spring 5 is preferably connected preferably made of hard rubber, are preferably inserted through the ground plate 1 between pairs of the protective apparatus, to keep the several springs of .each set in alinement, and to separate thesprings of each pair from the springs of the adjacent pairs. These insulating strips H are each provided with a shoulder 15 adapted to rest against the ground plate 1. The strips 14 14, taken in a series, are alternately inserted through the plate 1 in opposite directions, as shown in Fig. 5, so that the shoulders 15 on the first, third, fifth etc. bear against the plate l'on one side thereof, and those on the second, fourth, sixth, etc. bear against the plate 1 on the opposite side thereof. The
strips 14 14 are bound together bycontact rods 16 and 17 which extend through the series. When the strips 14 14v are thus bound together they are rigidly held in place,-due to the shoulders 15 15 on opposite sides of plate 1'. One of the rods 16 or 17 may be connected in circuit with an alarm 44 and battery lf), one terminal of the battery being connected to ground in a manner well understood, and the other rod 16 or 17 may be connected direct to ground When the protective apparatus operates, as shown on the left ofFig. 1, contacts 18 and 19 of spring tively, independently, dueto spring 4 being split as shown. An insulator 20 extends through springs 3, 4;, 5, and 6 of each set and is arranged so that the operation of springs 5 and 6 controls the operation of spring at, thereby causingcontacts 18 and 19 of spring 1 to firmly engage rods 16 and 17. Spring 4 engaging rods 16 and 17 also limits the extent of the operation of springs 5 and 6. Spring 4 isnormally out of contact .with
. rods 16 and 17, as shown on the right of Fig- 1. Line springs 3 3 terminate in line terminals 21 22 and switchboard springs (i b terminate in switchboard terminals 23 2-1, terminals and 24 being crossed over shown, to arrange line terminals 21 and 22 together and switchboard terminals 23 and 24: together. The line conductors are preferably connected to terminals 21 and confluctors leading to the central station switch board, in telephone systems or the like, are preferably connected to terminals 23 2 1. Line springs '3 3 are provided with. projections :25 25 thereon to form stops for the outer carbon blocks of the lightning arresters 8 8, to correspond with the stops formed by the ground plate 1 for the inner carbon blocks of the lightning arresters.
The operation of the protective apparatus is as follows: When an abnormally large current traverses a thermal protector for a sufiicient length of time, this current gener--.
ally coming from a line conductor through line spring 3, it heats the protector and finally softens er melts the heat-susceptible material securing the free end of grounded through line spring at, engage the rods 16 and 17, respecspring 5 to the protector 1t), and thereby allows spring 5 to release from the protector and operate with switchlmard spring 6 to the position shown on the left hand side of Fig. 1, thus (queuing ihecircuit between the line and switchboard and-thereby protecting the switchboard circuit and apparatus from the abnormally large current. Then length of time required to operate the thermal protector dcpends upon the strength of current traversing same. When springs I), and 6 operate as described, the movement of insulator 20 allows spring 4 to operate to the position shown on the left hand side of Fig. 1, so that contacts 18 and 19 thereof engage the oiulucting rods 16 and 17 and thereby grouinl the line spring 3 and close the alarm circuit between the said rods to actuate an alarm in the usual manner to indicate'the operation of the protective apparatus. it will be seen. that the line is now 3, spring 4 and ground rod 16, thus diverting the ob1ectionable current to earth. In case a bi hp'otential charge or comes in over a line wire, it will jump through the carbon lightning arrester 8 to the ground plate 1, in the usual manner. This open-circuit path to earth through the lightning arrcstcr S protects the switchboard and apparatus thereof from the highotential current or charge. \Vhen springfi eaves the thermal, protector, the solder in the an? nular recess at end 11 of the protector is disarranged to some extent and partially fills up the annular recess, becomingcool and solid in this position.
WV hen it is desired to reset the protector for another operation, the free end of spring 5 is depressed into the annular recess at end 11 of the protector and soldered therein.
as originally. This resoldcring may be accomplished in various ways, preferably, however, by an such as that forming the subject matter of my co pending application Serial No. 373,140, filed May 11, 1907, rhieh is a division of this present applicatit'iu The operation and resetting of the thermal protector may be repeated as many times as desired.
I do not wish to limit this invention to the exact details of construction as herein shown and described, as many modifications and changes may be made therein without departing from the scope of the appended claims.
The aceonmanyingdrawings simply illustrate one particular form of thermal proteeter and apparatus therefor for carrying out my invention.
What I claim as my invention, is:
1. In ter described.
strips inserted transversely through the current of electricity automatic resoldering device protective apparatus ofthe charac a mounting plate, msulatlng' gage the the corresp v other spring member by a solder connection,
'mounting plate, the said on one side of the said plate and carried by a thermal proprising acaciamounting plate and carrying conducting rods, a pair of s ring members suitably tector connected in circuit with the said spring members,- athird spring member mountedbetween the said pair of. springs and normally out of contact with the said rods, and means whereby the operation of the protector causes the said third spring member to engage the said rods.
2'. In apparatus of the class specified, a insulatingstrips carried by the said insulating strips, tector associated with the-apparatus for operation, and a spring member arranged to engage the said rods when the protector opcrates. v
3 Apparatus comprisingiathermal pro tector, I
upon abnormal current conditions in. the
circuit controlling 'means operable protector, a plurality of conducting rods associated with the I apparatus, and a spring member for engaging the said rods upon the operation of the apparatus.
4. Protective apparatus comprising a thermal protector and a. plurality of conducting rods associated therewith, means for operating the protector u on abnormal current conditions, and a'circuit-controlling member for engaging the said rods upon the operation of the protector. 1
, 5. Apparatus of the class specified comthermal protectors, a mounting plate therefor, means for suitably. operatin the protectors, a plurality of conducting ro s arranged parallel with. the said plate, anda series of spring members normally held out of contact-,with the said rods' by the said operating Imeans and each arranged to ensaid rods upon the operation of onding thermal protector.
.6. An electrothermal protector comprising conducting member, a heat cartridge removably mounted" on the saidconducting member, an operable spring member, an easily fusible metallic solder normally holding thesaid spring member under tension and connecting same with the heat cartridge for purposes substantiallyas described.
7. In apparatus of the class specified, a pair of spring membersp aheat cartridge electrically connected fro one of the spring members by a screw connection and to the and a third spring member normally con ,nected with one of the spring members of the pair by a separable contact.
8. Electrical protective apparatus comprising a'pair of conducting members and a thermal protector connected'to one said conducting member by a screw connection and to the other by a solder connection, and a third conducting member normallyelecplate, a plurality of conducting rods 'a mounting plate, a
normal conditions in the protector,
trically connected with one member of the said pair by a separable contact. a thermal pro- 9. Electrical protective" apparatus com prising a thermal protector electrically connected' in circuit with. a plurality of conducting members and having a screw connection between the protector and one of'the said conducting members, and another com ducting member normally electrically connected with one of the said plurality of conducting members by a separable contact.
10. In apparatus of the class specified,
pair of spring members mounted thereon, a thermal protector electrically connected with one springmember by a screw connection and with the other spring member by a solder connection adapt 'ed to be opened upon the operation of the device, and athird spring member normally connected with the outer spring of the pair by a separable contact, adapted to stay closed upon the operation of the device. I
11. In apparatus of the class specified, a mounting plate, conducting rods extending parallel with the said plate, a spring member carrying) spring mem er normally out of contact'with the said. rods, 'a third spring member normally soldered to the thermal protector, a fourth spring member normally in contact with the said third spring member, the said third and fourth spring members operating away from the mounting plate under ab and an insulating member coiiperating with the said spring members to cause the said second springmember to engage the said rods upon the operation of the apparatus.
l2. In apparatus of the class specified, a mounting plate, tion each provided with a shoulder to bear against the said plate andalternately inserted through same in opposite directions, a pair of conducting'rods on each side of the mounting late carried by the said insulating strips, suitable protective apparatus mounted in a mounting plate, and a series of spring 111cmbers on each side of the mounting plate each arranged to enga e the corresponding pair of conducting rods upon the operation of the protective apparatus; 7 v y 13. Apparatus of the class specified comprising a sprin member and a thermal protector coiiperatmg therewith, and a second spring member engaging the first at a cont-apt openable by pressing one spring member toward the other.
H. .In apparatus of the class specified, a pair of spring members, a thermal protector connected to one spring member by a solder connection,- a third spring member mounted outside ofthe pair, and a suitable contact between the said third spring and a spring of the pair adapted to be opened by a series ofstrips of insula-' so a thermal protector, a second.
series on each side. of the ipressing the said third spring toward the As inventor of the f0regoing,-I hereunto 10 pair. subscribe my name in the presence of two 15. A mounting, plate carrying a series of subscribing Witnesses this 5th dayof March, sets of protective apparatus,- a pair of con- 1906. 5* ducting rods arranged parallel with thesaid.
plate, and a spring member in each 'set to COOK engage the pair of rods upon the operation Witnesses: of the apparatus, the said rods and spring FREDERICK R. PARKER.
member constituting part of an alarm circuit. F. W. PAI-ZDEE.
US30492906A 1906-03-08 1906-03-08 Electrical protective apparatus. Expired - Lifetime US903812A (en)

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Application Number Priority Date Filing Date Title
US30492906A US903812A (en) 1906-03-08 1906-03-08 Electrical protective apparatus.
US373140A US870495A (en) 1906-03-08 1907-05-11 Automatic resoldering device for electrical protective apparatus.

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Application Number Priority Date Filing Date Title
US30492906A US903812A (en) 1906-03-08 1906-03-08 Electrical protective apparatus.

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US903812A true US903812A (en) 1908-11-10

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