US1915621A - Switch apparatus - Google Patents

Switch apparatus Download PDF

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Publication number
US1915621A
US1915621A US441759A US44175930A US1915621A US 1915621 A US1915621 A US 1915621A US 441759 A US441759 A US 441759A US 44175930 A US44175930 A US 44175930A US 1915621 A US1915621 A US 1915621A
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Prior art keywords
base
blow
coils
contact
disposed
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US441759A
Inventor
William M Scott
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ITE Circuit Breaker Co
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ITE Circuit Breaker Co
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Publication date
Priority to GB191400582D priority Critical patent/GB191400582A/en
Priority claimed from US354480A external-priority patent/US1914582A/en
Application filed by ITE Circuit Breaker Co filed Critical ITE Circuit Breaker Co
Priority to US441759A priority patent/US1915621A/en
Application granted granted Critical
Publication of US1915621A publication Critical patent/US1915621A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/30Means for extinguishing or preventing arc between current-carrying parts
    • H01H9/44Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet

Definitions

  • gral as by molding, withthe switch mounting panel, or base,-and a cup-like member or cover detachable with respect to said base and forming with said partition or wall an enclosure for a blow-out coil.
  • My invention further resides in apparatus of the character hereinafter described andclaimed.
  • FIG. 1 is a side elevational view of switch apparatus constructed in accordance with my invention
  • Fig. 2 is an elevational view of one of the parts
  • Fig. 3 is an end elevational View, looking toward the left in Fig. 2;
  • Fig. 4 is a sectional view, the section taken on the line 4-4 in Fig. 9.;
  • Fig. 5 is a front elevational View of a pair' of magnetic blow-out coils
  • Fig. 6 is a side elevational View, looking toward the left in Fig. '5;
  • Fig. 7 is a front elevational view partly broken away, looking toward the left in Fig. 1;
  • Fig. 8 is a fragmentary view taken from Fig. 7, some of the parts removed.
  • Fig. 9 is a.plan'view partly in section the section taken on line 9-9 in Fig. 8.
  • a base or panel 10f suitable insulating material is provided with barriers 1a extending transversely thereto and has mounted.
  • electrical switch vapparatus comprising a stationary contact 2 suitably secured to the base, as by a conducting stud 3 which comprises a lead conductor of the circuit to be protected, and a movable contact 4 mounted upon a transversely extending bar or support 5, and electrically connected by a flexible conducting strip 6 to a terminal 7 on the bracket 8 secured to base 1.
  • Terminal 7 is connected to one end of an overload coil 9 whose other end is connected to the conducting stud 10 comprising the other lead from the circuit to be protected.
  • auxiliary or arcing contact 11 carried on the end of a resilient conducting arm 12.
  • contact 11 isin engagement with a contact 13 suitably secured to the base, as by screw 13a, which is positionedand spaced with respect to con tact 2 by a raised portion or boss 13b forming a part of the base.
  • Means for extinguishing the are between contacts 11 and 13, referring more particularly to Figs. 5 and 6, comprises a pair of blow-out coils 14 and 15 arranged on each side of the contacts in the usual manner, and having their inner ends connected to each other by a conducting strip or bridge 16,
  • Conducting strip 16 is suitably secured to the base by contact 13 and-is in electrical contact therewith.
  • the conducting strip 17 is likewise clamped to the base by contact 2, the extension of which passes through aperture 18, thereby connecting coils 14 and 15 in parallel between contacts 2 and 13.
  • Insulating enclosing structure for the blowout coils comprises partitions or walls 19 preferably integrally mounted to the base or panel 1 as by moulding, and of substantially the same material, and cover members 20 of arc-resisting material detachably secured with respect to the base and partition s.
  • cover members 20 of arc-resisting material detachably secured with respect to the base and partition s.
  • an individual pair of blow-out coils are disposed adjacent the opposing faces of two partitions or walls, and are suitablyhoused by the cup-like covers 20 which form with partitions 19 receptacles.
  • the members 19 form common wall structure for a pair of unrelated coils.
  • Each (partition or wall 19, as previously mentione is preferably moulded to base 1, forming an integral part therewith, and is generally of insulating material of inferior arc-resisting characteristics to that used in the cover members 20. Accordingly, the cover members are so designed that they alone are subjected to the intense heat of the are.
  • the cover members 20 are each provided with oifset portions 21, Figs.
  • each cover member 20 is provided with a shoulder 22 extending along three sides of the same for engaging the corresponding edges of a partition 19 to relatively position the same.
  • the edges of the cover abutting base 1 seat within a correspondingly shaped depression-20d in the base 1 and have a pair of notches 23 and 24 therein for recelving the bridgin conductors 16 and 17 respectively of the b ow-out coils.
  • the front side of the cover partially'overlying the outer edge of the partition is provided with a semicircular notch 25 and a longitudinally extending recess 26 for receiving a holding screw 27 and a clamp 28.
  • Screw 27 is secured, as by an insert 27a, to the front edge of partition 19 and serves to clamp the front of cover 20 to the partition.
  • two of the partitions 19, when three pairs of blow-out 00118 are employed have a cover member mounted on each side thereof and clamped thereto by common clampin structure 27 and-28. Accordingly, quick and easy'accessto the. blow-out coils mayzbe accomplished by simply unloosening screw 27.
  • the main movable contact member 4 In the opening movement of the circuit breaker, the main movable contact member 4 is first withdrawn from the fixed contact 2; while for the. instant, movable contact 11 maintains its engagement with fixed contact -13, thus bringing the blow-out coils into series with the main circuit and thereby rendering them effective to ru ture the are drawn in the-space between t em incident upon the further opening of the switch and consequent withdrawal of contact 11 from engagement with contact 13.
  • the impedance of the blow-out coils shall be a minimum consistent with the defiired said attained by disposing the two coils on opposite sides of the arcing chamber, the effectiveness thus secured being such that iron may be altogether omitted from the magnetic circuit and coils of relatively few turns are found to sufiice.
  • the cover members 20 which shield .the blow-out coils, the' partition members 19, and the base area above the contact 13, are of material having high arc-resisting characteristics; accordingly, base 1 and partitions 19, being efl'ectively shielded fromv arcing, the material from which these are moulded may be selected with reference to its insulating qualities rather than 1 for its ability to resist arcing.
  • Switch apparatus comprising a plurality of sets of coacting stationary and movable contacts, pairs of blow-out coils between which said sets of contacts'are respectively disposed, enclosing structure 'for coils related to different sets of contacts, and a partition member between the coils in said structure and whose plane is substantially parallel to the plane of movement of the movable contacts, said enclosing structure comprising'a cover member detachably mounted with respect to said partition member.
  • a base member provided with a wall-like ortion extending laterally outwardly there rom, a cover member complementary to said base member and said portion thereof and fitted to the same to provide therewith a chamber, and a blow-out coil disposed in said chamber.
  • a base member provided with a wall-likeportion extending laterally outwardly therefrom, a cover member complementary to said base member and said portion thereof and fitted to the same to provide therewith a chamber,- means detachably holding said cover member in assembled relation with res ect to said base member and ortion thereof, and a blow-out coil dispose in said chamber.
  • a base member provided with a. wa l-like portion extending laterally outwardly therefrom, a cover member complementary to said base member and said. portion thereof and fitted to the same to provide therewith a chamber, means detachably holding said cover member in assembled -relafor movement between said cover members bers reversed with respect to each other and v disposed on opposite sides of said portion and roviding therewith chambers, means detac ably holding said cover members in assembled relation with respect to said portion, and blow-out coils disposed respectively in said chambers.
  • a base member provided with a wall-like portion extending laterally outwardly therefrom, cover members reversed with respect to each other and disposed on opposite sides of said portion and providing therewith chambers, means engaging said portion and common with respect to said cover members and operating to hold the latter in assembled relation with respect to said portion, and blow-out coils disposed respectively in said chambers.
  • a base member provided with avwall-like portion extending laterally outwardly therefrom, cover members reversed with respect to each other and disposed on opposite sides of said portion and providing therewith chambers, a clamping element common with respect to said cover members and engaging adjacent edge portions 'of the latter to clamp the same-in assembled relation with respect to said wall portion, and a screw extending through said element and screwed into said wall portion.
  • a base member provided with spaced wall-like portions eX-' tending laterally outwardly therefrom, cover members complementary respectively to said portions and the base member and fitted to the latter and the respective associated wall portions thereof to provide with the same chambers, complementary switch contacts disposed intermediate said cover members, and blow-out coils disposed in said chambers and jointly effective to cause blowingout of arcs occurring upon disengagement of sald contacts, said cover members provided with complementary abutting portions providing a protective shield for said base member from such arcs.
  • Structure for controlling an are com-' prising, barrier structure of insulating material, a wall element, of different material having high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, and magnetic blow-out structure disposed between said barrier structure and said" wall element.
  • Structure for controlling an are comprising, barrier structure of insulating material, a wall element, of different material having; high arc-resisting characteristics, disposed between the region in whichthe arc is drawn and said barrier structure, magnetic blow-out structure disposed between said barrier structure and said wall element, and means for detachably securing said wall element to said barrier structure.
  • Structure for controlling an arc co mprising, barrier structure of insulating material, a wall element, of different material having high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, magnetic blow-out structure disposed between said barrier structure and said well element, and means shielded from the are for detachably securing said wall element to said barrier structure.
  • Structure for controlling an comprising, barrier structure of insulating material, a wall element, of different material having, high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, an irouless core blow-out c011 d1sposed between sald barrier and said wall element, and means shielded from said are by said wall element for detachably securing said wall element to said barrier structure.
  • a circuit breaker comprising a base, fixed contact structure mounted on the front thereof, contact structure movable toward and away from said base into and out of engagement with said fixed contact strucand away from said base into and out of contact with said fixed contact structure, ironless core blow-out coils having their axes parallel to said base'and intercepting the path of movement of said movable contact structure, individual encasing members for said blow-out coils of arc-resistant material and removable forwardly from said base independently of displacement of said fixed contact structure, and means for releasably holding said encasing members accessible from the front of said base.

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  • Arc-Extinguishing Devices That Are Switches (AREA)

Description

June 27, 1933. w, scar-r 1,915,621
SWITCH APPARATUS Original Filed April 12. 1929 2 Sheets-Sheet 1 I P? p 2/ l5 I I I I I i i g T :2 27a. 7 firi- 28 26 2 2 INVENT {WM 4. w
{ ATTORNEY June 27, 1933. w. M. scoTT SWITCH APPARATUS Original Filed April 12, 1929 2 Sheets-Sheet 2 INVENTOR 1 ATTORNEY Patented June 27, 1933 UNITED STATES PATENT OFFICE WILLIAM E. SCOTT, F TREDYFFRIN TOWNSHIP, CHESTER COUNTY, PENNSYLVANIA,
ASSIGNOR TO I-T-E CIRCUIT BREAKER COMPANY, OF PHILADELPHIA, PENNSYL- VANIA, .A. CORPORATION OF NEW JERSEY SV ITCH APPARATUS Original application filed April 12, 1929, Serial No. 354,480. Divided and this application filed April 5, 1930, Serial No. 441,759. Renewed November 17, 1931.
gral, as by molding, withthe switch mounting panel, or base,-and a cup-like member or cover detachable with respect to said base and forming with said partition or wall an enclosure for a blow-out coil.
My invention further resides in apparatus of the character hereinafter described andclaimed.
For an understanding of my invention,
reference is had to the accompanying drawings, in which I Fig. 1 is a side elevational view of switch apparatus constructed in accordance with my invention; v
Fig. 2 is an elevational view of one of the parts; 1
Fig. 3 is an end elevational View, looking toward the left in Fig. 2;
' Fig. 4 is a sectional view, the section taken on the line 4-4 in Fig. 9.;
Fig. 5 is a front elevational View of a pair' of magnetic blow-out coils Fig. 6 is a side elevational View, looking toward the left in Fig. '5;
Fig. 7 is a front elevational view partly broken away, looking toward the left in Fig. 1;
Fig. 8 is a fragmentary view taken from Fig. 7, some of the parts removed; and
Fig. 9 is a.plan'view partly in section the section taken on line 9-9 in Fig. 8.
Referring to Figs. 1 and 7, a base or panel 10f suitable insulating material, is provided with barriers 1a extending transversely thereto and has mounted. thereon electrical switch vapparatus comprising a stationary contact 2 suitably secured to the base, as by a conducting stud 3 which comprises a lead conductor of the circuit to be protected, and a movable contact 4 mounted upon a transversely extending bar or support 5, and electrically connected by a flexible conducting strip 6 to a terminal 7 on the bracket 8 secured to base 1. Terminal 7 is connected to one end of an overload coil 9 whose other end is connected to the conducting stud 10 comprising the other lead from the circuit to be protected.
Cooperating with movable contact 4, and a mounted also upon the switch arm support 5 is an auxiliary or arcing contact 11 carried on the end of a resilient conducting arm 12. In the closed position of the switch, contact 11 isin engagement with a contact 13 suitably secured to the base, as by screw 13a, which is positionedand spaced with respect to con tact 2 by a raised portion or boss 13b forming a part of the base. Means for extinguishing the are between contacts 11 and 13, referring more particularly to Figs. 5 and 6, comprises a pair of blow-out coils 14 and 15 arranged on each side of the contacts in the usual manner, and having their inner ends connected to each other by a conducting strip or bridge 16,
and their outer ends connected together by a conducting strip 17 having a rectangular opening 18 therein for a purpose hereinafter described. Conducting strip 16 is suitably secured to the base by contact 13 and-is in electrical contact therewith. The conducting strip 17 is likewise clamped to the base by contact 2, the extension of which passes through aperture 18, thereby connecting coils 14 and 15 in parallel between contacts 2 and 13.
Insulating enclosing structure for the blowout coils, re erring more particularly to Figs. 2, 3, 4,8 and 9, comprises partitions or walls 19 preferably integrally mounted to the base or panel 1 as by moulding, and of substantially the same material, and cover members 20 of arc-resisting material detachably secured with respect to the base and partition s. As viewed in Figs. 8 and 9, an individual pair of blow-out coils are disposed adjacent the opposing faces of two partitions or walls, and are suitablyhoused by the cup-like covers 20 which form with partitions 19 receptacles.
' for completely enclosing the blow-out coils. Except for the end walls, the members 19 form common wall structure for a pair of unrelated coils. Each (partition or wall 19, as previously mentione is preferably moulded to base 1, forming an integral part therewith, and is generally of insulating material of inferior arc-resisting characteristics to that used in the cover members 20. Accordingly, the cover members are so designed that they alone are subjected to the intense heat of the are. To this end, the cover members 20 are each provided with oifset portions 21, Figs. 3 and 4, adapted to abut each other when the covers .are in position to shield and .protect an appropriate portion of base 1 not shielded by the contact 13, and to furthermore space the cover members from each other to provide suitable clearance for the movable contact element between the same. The interior of each cover member 20 is provided with a shoulder 22 extending along three sides of the same for engaging the corresponding edges of a partition 19 to relatively position the same. The edges of the cover abutting base 1 seat within a correspondingly shaped depression-20d in the base 1 and have a pair of notches 23 and 24 therein for recelving the bridgin conductors 16 and 17 respectively of the b ow-out coils. The front side of the cover partially'overlying the outer edge of the partition is provided with a semicircular notch 25 and a longitudinally extending recess 26 for receiving a holding screw 27 and a clamp 28. Screw 27 is secured, as by an insert 27a, to the front edge of partition 19 and serves to clamp the front of cover 20 to the partition. As viewed in 1 g. 9, two of the partitions 19, when three pairs of blow-out 00118 are employed, have a cover member mounted on each side thereof and clamped thereto by common clampin structure 27 and-28. Accordingly, quick and easy'accessto the. blow-out coils mayzbe accomplished by simply unloosening screw 27.
and clamp 28.
In the opening movement of the circuit breaker, the main movable contact member 4 is first withdrawn from the fixed contact 2; while for the. instant, movable contact 11 maintains its engagement with fixed contact -13, thus bringing the blow-out coils into series with the main circuit and thereby rendering them effective to ru ture the are drawn in the-space between t em incident upon the further opening of the switch and consequent withdrawal of contact 11 from engagement with contact 13.
. v 11 order to prevent arcing at the main contacts of the circuit breaker, it. is essential that. the impedance of the blow-out coils shall be a minimum consistent with the defiired said attained by disposing the two coils on opposite sides of the arcing chamber, the effectiveness thus secured being such that iron may be altogether omitted from the magnetic circuit and coils of relatively few turns are found to sufiice. The cover members 20 which shield .the blow-out coils, the' partition members 19, and the base area above the contact 13, are of material having high arc-resisting characteristics; accordingly, base 1 and partitions 19, being efl'ectively shielded fromv arcing, the material from which these are moulded may be selected with reference to its insulating qualities rather than 1 for its ability to resist arcing.
This application is a division of my copending application, Serial No. 354,480, filed A ril12,1929.
he invention claimed is:
1. Switch apparatus comprising a plurality of sets of coacting stationary and movable contacts, pairs of blow-out coils between which said sets of contacts'are respectively disposed, enclosing structure 'for coils related to different sets of contacts, and a partition member between the coils in said structure and whose plane is substantially parallel to the plane of movement of the movable contacts, said enclosing structure comprising'a cover member detachably mounted with respect to said partition member.
' 2. ary contact, a movable contact coating therewith, a pair of blow-out coils between which said contacts are disposed, an enclosing structure for each of said coils comprising a-wal1 member of insulating material whose plane is substantially parallel to the plane of movement of the'movable contact and a cover member fitted to said wallmember.
3. In switch apparatus, a base member provided with a wall-like ortion extending laterally outwardly there rom, a cover member complementary to said base member and said portion thereof and fitted to the same to provide therewith a chamber, and a blow-out coil disposed in said chamber.
4. In switch apparatus, a base member provided with a wall-likeportion extending laterally outwardly therefrom, a cover member complementary to said base member and said portion thereof and fitted to the same to provide therewith a chamber,- means detachably holding said cover member in assembled relation with res ect to said base member and ortion thereof, and a blow-out coil dispose in said chamber.
5. In switch apparatus, a base member provided with a. wa l-like portion extending laterally outwardly therefrom, a cover member complementary to said base member and said. portion thereof and fitted to the same to provide therewith a chamber, means detachably holding said cover member in assembled -relafor movement between said cover members bers reversed with respect to each other and v disposed on opposite sides of said portion and roviding therewith chambers, means detac ably holding said cover members in assembled relation with respect to said portion, and blow-out coils disposed respectively in said chambers.
8. In switch apparatus, a base member provided with a wall-like portion extending laterally outwardly therefrom, cover members reversed with respect to each other and disposed on opposite sides of said portion and providing therewith chambers, means engaging said portion and common with respect to said cover members and operating to hold the latter in assembled relation with respect to said portion, and blow-out coils disposed respectively in said chambers.
9. In switch apparatus, a base member provided with avwall-like portion extending laterally outwardly therefrom, cover members reversed with respect to each other and disposed on opposite sides of said portion and providing therewith chambers, a clamping element common with respect to said cover members and engaging adjacent edge portions 'of the latter to clamp the same-in assembled relation with respect to said wall portion, and a screw extending through said element and screwed into said wall portion.
10. In switch vapparatus, a base member provided with spaced wall-like portions eX-' tending laterally outwardly therefrom, cover members complementary respectively to said portions and the base member and fitted to the latter and the respective associated wall portions thereof to provide with the same chambers, complementary switch contacts disposed intermediate said cover members, and blow-out coils disposed in said chambers and jointly effective to cause blowingout of arcs occurring upon disengagement of sald contacts, said cover members provided with complementary abutting portions providing a protective shield for said base member from such arcs.
11. Structure for controlling an are com-' prising, barrier structure of insulating material, a wall element, of different material having high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, and magnetic blow-out structure disposed between said barrier structure and said" wall element.
12. Structure for controlling an are comprising, barrier structure of insulating material, a wall element, of different material having; high arc-resisting characteristics, disposed between the region in whichthe arc is drawn and said barrier structure, magnetic blow-out structure disposed between said barrier structure and said wall element, and means for detachably securing said wall element to said barrier structure.
13. Structure for controlling an arc co mprising, barrier structure of insulating material, a wall element, of different material having high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, magnetic blow-out structure disposed between said barrier structure and said well element, and means shielded from the are for detachably securing said wall element to said barrier structure.
1-1. Structure for controlling an are comprising, barrier structure of insulating material, a wall element, of different material having, high arc-resisting characteristics, disposed between the region in which the arc is drawn and said barrier structure, an irouless core blow-out c011 d1sposed between sald barrier and said wall element, and means shielded from said are by said wall element for detachably securing said wall element to said barrier structure.
15. A circuit breaker comprising a base, fixed contact structure mounted on the front thereof, contact structure movable toward and away from said base into and out of engagement with said fixed contact strucand away from said base into and out of contact with said fixed contact structure, ironless core blow-out coils having their axes parallel to said base'and intercepting the path of movement of said movable contact structure, individual encasing members for said blow-out coils of arc-resistant material and removable forwardly from said base independently of displacement of said fixed contact structure, and means for releasably holding said encasing members accessible from the front of said base.
WILLIAM M. SCOTT.
US441759A 1914-01-08 1930-04-05 Switch apparatus Expired - Lifetime US1915621A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB191400582D GB191400582A (en) 1914-01-08 1914-01-08 Improvements relating to Stabilising Apparatus for Ships.
US441759A US1915621A (en) 1929-04-12 1930-04-05 Switch apparatus

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US354480A US1914582A (en) 1929-04-12 1929-04-12 Electrical switching apparatus
US441759A US1915621A (en) 1929-04-12 1930-04-05 Switch apparatus

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2555799A (en) * 1947-02-05 1951-06-05 Allis Chalmers Mfg Co Electric switch

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2555799A (en) * 1947-02-05 1951-06-05 Allis Chalmers Mfg Co Electric switch

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