US2546366A - Switch - Google Patents

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US2546366A
US2546366A US745196A US74519647A US2546366A US 2546366 A US2546366 A US 2546366A US 745196 A US745196 A US 745196A US 74519647 A US74519647 A US 74519647A US 2546366 A US2546366 A US 2546366A
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United States
Prior art keywords
blades
contact
switch
posts
springs
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Expired - Lifetime
Application number
US745196A
Inventor
Eola A Lindae
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EOLA LINDAE
JOSEPH P POHRER
Original Assignee
EOLA LINDAE
JOSEPH P POHRER
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Filing date
Publication date
Priority claimed from US692341A external-priority patent/US2511354A/en
Application filed by EOLA LINDAE, JOSEPH P POHRER filed Critical EOLA LINDAE
Priority to US745196A priority Critical patent/US2546366A/en
Application granted granted Critical
Publication of US2546366A publication Critical patent/US2546366A/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
    • H01H31/00Air-break switches for high tension without arc-extinguishing or arc-preventing means
    • H01H31/26Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch
    • H01H31/28Air-break switches for high tension without arc-extinguishing or arc-preventing means with movable contact that remains electrically connected to one line in open position of switch with angularly-movable contact
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00Contacts
    • H01H1/58Electric connections to or between contacts; Terminals
    • H01H1/5833Electric connections to or between contacts; Terminals comprising an articulating, sliding or rolling contact between movable contact and terminal

Definitions

  • the usual knife switch comprises a single blade for each circuit to be made or broken, that is, a single-pole switch comprises one blade hingedly engaged at one end between contacts pressing against both sides of the blade, which end is called the hinge jaw, and rotatably engaging and disengaging at the other end opposed spring contacts, called the break jaw.
  • a pair of parallel blades is employed, which engage between them, at both the hinge and the break ends, clips with sphericallyrounded contact faces.
  • the primary ob ect of the present invention is to provide a double knife-type electrical switch with spherical contact surfaces interposed between the blades at both the hinge and the break ends.
  • a further object of the present invention is to provide a switch having a plurality of spherical contact surfaces which in the actuation of the switch connect and disconnect quickly and positively.
  • An additional object of the present invention is to provide a switch with spherically-formed contact or bearing points reinforced with silver or other metal suitable for long-wearing electrical contacts.
  • Another object of the present invention is to provide a high-capacity electrical switch whose current-transmitting parts may be economically fabricated from fiat metal, and are readily assembled and easily replaced.
  • a further object of ..'the present invention is to provide a. 'switch'of the type stated'h'aving air i ventilated contact, posts for. readily dissiparing" heat generated'by contact, arcing and current conduction.
  • Figure 3 is a vertical sectional view taken along line 3-3 of Figure 2;
  • A designates a switch comprising two pot-type
  • porcelain insulators l conventionally mounted in suitably spaced relation upon the steelwork of a transmission tower or some other supporting structure (not shown). Molded, or otherwise mounted in and projecting upwardly from the insulators l are studs 2, and mounted thereon by means of nuts 3 are copper terminal blocks 4 having binding posts 5 for the attachment of buss bars 6. The inner ends of terminal blocks 4 areprovided with a pair of parallel milled slots v1v fortightly receiving upright contact posts 8, the latter being retained therein by press-fitted pins 9 passing through laterally drilled apertures Hi, It, in contact blocks 4 and posts 3, respectively.
  • Each of said contact posts 8 consists of. two halves symmetrically formed from flat copper stock, their upper end-portions I! being bent inwardly and mitered to bear tightly against each other and thereby be retained in spaced parallel relation to permit the free circulation of air therebetween for ventilation purposes. Beneath their inwardly bent upper-end portions H, the contact posts 8 are outwardly drawn, pressed, stamped or embossed in the provision of protruding spherical portions [2, at the outer, or contacting, surfaces of which are silver inserts l3.
  • Each pair of matching spherical portions l2 of the two symmetrically opposed halves of each post together form a substantially ball-like contact, the surface of which is concentric with the vertical plane along which the mitered upper end-portions ll meet.
  • there are four such ball-like con tacts although more or less than four may readily be employed where desired.
  • the posts 8 fixedly attached to the insulators i at both the hinge end (shown at right in Figure 1) and the break" end (shown at left in Figure 1) are substantially identical.
  • contact post fl is laterally drilled as at to receive hinge bolt l5 which, by means .of
  • radially split spring washers I5 and nut [1, holds the blades IS with adjustable tension against'the silver contact inserts l3 of the contact post 8 at that end.
  • ter minal block 4 is tapped to receive bolts [9 secure ing to it the fixed latch keeper 2!).
  • the break ends of blades is are laterally drilled near their extremities to receive bolt 2
  • the latch lever is provided with a ringshaped latch handle 26.
  • also passes through, and together with nut 22 holds adjacent to the outer surfaces of blades l8, leaf springs 2! having bent outer ends 28 and inwardly protruding embossed spherical portion 29 whereby to space said springs 2'! with reference to the outer surfaces of blades 18.
  • tending through the break ends of blades 58 is a bolt 30 provided at its threaded end with a nut 3i for connecting the inner ends of leaf springs 21.
  • An electrical switch comprising a dielectric base-forming means, terminal ventilated contact posts mounted thereon in spaced relation to each other, a pair of blades, one on each side of said clips, a hinge bolt attaching one end of said blades to one of said contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact post, leaf springs operatively mounted upon the blades and having inwardly-protruding surfaces for abutment against the outer surfaces of the blades, and an adjustable tension bolt connecting said springs.
  • Anelectrical switch comprising a dielectric base-forming means, terminal contact posts having spaced parallel portions mitered together at their upper ends and mounted on said base-forming means in spaced relation to each other, a pair of blades, said blades being disposed on opposite sides of the contact posts, a hinge bolt attaching one end of said blades to one of said contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of Also mounted in and ex- By adjusting nut 3!, any desired amount of spring pressure may be exerted by the inwardlycontact with the other contact post, and leaf springs mounted on the outer surfaces of said blades, said springs having bent outer ends and inwardly projecting surfaces for spacing the springs in reference to the outer surfaces of the blades.
  • An electrical switch comprising a dielectric base-forming means, terminal contact posts having spaced parallel portions mitered together at their upper ends and mounted on said base-forming means in spaced relation to each other, a pair of blades, said blades being disposed on opposite sides of the contact posts, a hinge bolt attaching one end of said blocks to one of said contact posts, spring washers mounted on the ends of said hinge bolt for holding the blades with adjustable tension against the contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact post, leaf springs mounted on the outer surfaces of said blades, said springs having bent outer ends and inwardly-projecting surfaces for spacing the Springs in reference to the blades, and an adjusting bolt extending through the blades and connecting the inner ends of the leaf springs for regulating the amount of spring pressure exerted by the inwardly-projecting surfaces of the springs upon the blade.
  • a leaf spring mounted on the outer surface of each of said blades, said spring having a bent outer end and an inwardly projecting surface for abutment against the outer surface of the blade whereby the spring is spaced in reference to the blade, and an adjusting bolt extending through the blade and connecting the inner ends of the leaf springs for regulating the amount of spring pressure exerted by the inwardly projecting surface of the springs upon the blade.
  • An electrical switch comprising a pair of spaced terminal contact posts having spaced parallel portions mitered together at their upper ends, a pair of blades, said blades being disposed on opposite sides of the contact posts, one end of said blades being hingedly mounted upon one of said contact posts, spring washers disposed against the outwardly presented faces of the v hinged end of said blades for holding the blades with adjustable tension against the contact posts, and resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact posts.

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Description

March 27, 1951 QH, NDAE 2,546,366
SWITCH I Original Filed Aug. '22, 1946 FIG. I
INVENTOR. WILLIAM H.L|NDAE DECEASED gmdw-fmu r \w v ATTO RN EY.
' BY EOLA A.LINDAE ADMINISTRATRlX,d b n Patented Mar. 27, 1951 2,546,366 FlCE:
SWITCH William H. Lindae, deceased, late of St. Louis, Mo., by Eola A. Lindae, administratrix de bonis non, St. Louis, Mo.; said William H. Lindae assignor of one-half to Eola Lindae and onehalf to Joseph P. Pohrer Original application August 22, 1946, Serial No. 692,341, now Patent No. 2,511,354, dated June 13, 1950. Divided and this application May 1,
1947, Serial No. 745,196
(ill. 200-162) Claims.
, This invention relates in' general to certain new and useful improvements in electrical switches, and more particularly, to those of the knife type, and is a division of application Serial No. 692,341, filed August 2 1946, now Patent No. 2,511,354, June 13, 1950. The usual knife switch comprises a single blade for each circuit to be made or broken, that is, a single-pole switch comprises one blade hingedly engaged at one end between contacts pressing against both sides of the blade, which end is called the hinge jaw, and rotatably engaging and disengaging at the other end opposed spring contacts, called the break jaw. In the invention, however, a pair of parallel blades is employed, which engage between them, at both the hinge and the break ends, clips with sphericallyrounded contact faces. The primary ob ect of the present invention is to provide a double knife-type electrical switch with spherical contact surfaces interposed between the blades at both the hinge and the break ends.
A further object of the present invention is to provide a switch having a plurality of spherical contact surfaces which in the actuation of the switch connect and disconnect quickly and positively. v
An additional obiect of the present invention is to provide a switch with spherically-formed contact or bearing points reinforced with silver or other metal suitable for long-wearing electrical contacts.
,- Another object of the present invention is to provide a high-capacity electrical switch whose current-transmitting parts may be economically fabricated from fiat metal, and are readily assembled and easily replaced.
' A further object of ..'the present invention is to provide a. 'switch'of the type stated'h'aving air i ventilated contact, posts for. readily dissiparing" heat generated'by contact, arcing and current conduction.
The above and other objects will become more fully apparent from the following specification, which, by way of illustration rather than limitation, sets forth preferred processes and preferred forms of apparatus constituting embodiments of the present invention, the scope of which is defined in" the appended claims. 7 In the accompanying drawings: --Figure l is a top plan view of a switch constructed in accordance with and embodying the invention; I {V ;Figure 2 is a side elevational view of the switch, the open or disconnected position thereof being indicated in dot-dash lines;
Figure 3 is a vertical sectional view taken along line 3-3 of Figure 2; and
. A designates a switch comprising two pot-type,
porcelain insulators l conventionally mounted in suitably spaced relation upon the steelwork of a transmission tower or some other supporting structure (not shown). Molded, or otherwise mounted in and projecting upwardly from the insulators l are studs 2, and mounted thereon by means of nuts 3 are copper terminal blocks 4 having binding posts 5 for the attachment of buss bars 6. The inner ends of terminal blocks 4 areprovided with a pair of parallel milled slots v1v fortightly receiving upright contact posts 8, the latter being retained therein by press-fitted pins 9 passing through laterally drilled apertures Hi, It, in contact blocks 4 and posts 3, respectively.
Each of said contact posts 8 consists of. two halves symmetrically formed from flat copper stock, their upper end-portions I! being bent inwardly and mitered to bear tightly against each other and thereby be retained in spaced parallel relation to permit the free circulation of air therebetween for ventilation purposes. Beneath their inwardly bent upper-end portions H, the contact posts 8 are outwardly drawn, pressed, stamped or embossed in the provision of protruding spherical portions [2, at the outer, or contacting, surfaces of which are silver inserts l3. Each pair of matching spherical portions l2 of the two symmetrically opposed halves of each post together form a substantially ball-like contact, the surface of which is concentric with the vertical plane along which the mitered upper end-portions ll meet. In the preferred embodiment shown, there are four such ball-like con tacts, although more or less than four may readily be employed where desired.
It will be noted that the posts 8 fixedly attached to the insulators i at both the hinge end (shown at right in Figure 1) and the break" end (shown at left in Figure 1) are substantially identical. However, at the so-called hinge end, contact post fl is laterally drilled as at to receive hinge bolt l5 which, by means .of
radially split spring washers I5 and nut [1, holds the blades IS with adjustable tension against'the silver contact inserts l3 of the contact post 8 at that end. At the other, or break end, ter minal block 4 is tapped to receive bolts [9 secure ing to it the fixed latch keeper 2!).
'The break ends of blades is are laterally drilled near their extremities to receive bolt 2| which, together with nut 22, holds between said blades [8 a channel-shaped spacer 23 and a rock- 3 ably mounted latch lever 28 having a hook adapted to engage the latch keeper 20. At its upper end, the latch lever is provided with a ringshaped latch handle 26. Bolt 2| also passes through, and together with nut 22 holds adjacent to the outer surfaces of blades l8, leaf springs 2! having bent outer ends 28 and inwardly protruding embossed spherical portion 29 whereby to space said springs 2'! with reference to the outer surfaces of blades 18. tending through the break ends of blades 58 is a bolt 30 provided at its threaded end with a nut 3i for connecting the inner ends of leaf springs 21.
extending spherical portions 29 of springs 27 against the out-er surfaces of blades E5 in the vicinity of the engagement and electrical contact of their inner surfaces with the interposed contact post 8 at the break end of the switch.
The method of assembly and disassembly of the switch for the replacement of parts is apparent from the construction shown and correct alignment of the parts follows inherently from the spring pressures against the several spherical contact surfaces.
Switches constructed as disclosed herein, whether of the single-pole single-throw type as illustrated or of more complex detail, as of multiple-pole, double-throw type, operate with a minimum of friction, due to the ball-like contacts. This permits higher contact pressures, which, together with the self-aligning feature, results in more positive electrical contacts than would otherwise be possible. At the break end of the switch, the movement of the blades into and out of engagement with the several spherical contact faces is progressive, so that the contact is made and broken quickly.
It should be understood that changes and modifications both in the methods as well as in the form, construction, arrangement and combination of the several parts of the switch may be made and substituted for those herein shown and described without departing from the nature and principle of the present invention.
Having thus described the invention, what is claimed and desired to secure by Letters Patent is:
1. An electrical switch comprising a dielectric base-forming means, terminal ventilated contact posts mounted thereon in spaced relation to each other, a pair of blades, one on each side of said clips, a hinge bolt attaching one end of said blades to one of said contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact post, leaf springs operatively mounted upon the blades and having inwardly-protruding surfaces for abutment against the outer surfaces of the blades, and an adjustable tension bolt connecting said springs.
2. Anelectrical switch comprising a dielectric base-forming means, terminal contact posts having spaced parallel portions mitered together at their upper ends and mounted on said base-forming means in spaced relation to each other, a pair of blades, said blades being disposed on opposite sides of the contact posts, a hinge bolt attaching one end of said blades to one of said contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of Also mounted in and ex- By adjusting nut 3!, any desired amount of spring pressure may be exerted by the inwardlycontact with the other contact post, and leaf springs mounted on the outer surfaces of said blades, said springs having bent outer ends and inwardly projecting surfaces for spacing the springs in reference to the outer surfaces of the blades.
3. An electrical switch comprising a dielectric base-forming means, terminal contact posts having spaced parallel portions mitered together at their upper ends and mounted on said base-forming means in spaced relation to each other, a pair of blades, said blades being disposed on opposite sides of the contact posts, a hinge bolt attaching one end of said blocks to one of said contact posts, spring washers mounted on the ends of said hinge bolt for holding the blades with adjustable tension against the contact posts, resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact post, leaf springs mounted on the outer surfaces of said blades, said springs having bent outer ends and inwardly-projecting surfaces for spacing the Springs in reference to the blades, and an adjusting bolt extending through the blades and connecting the inner ends of the leaf springs for regulating the amount of spring pressure exerted by the inwardly-projecting surfaces of the springs upon the blade.
4. In an electrical switch having spaced terminal contact posts and a pair of blades disposed on opposite sides of the contact posts, a leaf spring mounted on the outer surface of each of said blades, said spring having a bent outer end and an inwardly projecting surface for abutment against the outer surface of the blade whereby the spring is spaced in reference to the blade, and an adjusting bolt extending through the blade and connecting the inner ends of the leaf springs for regulating the amount of spring pressure exerted by the inwardly projecting surface of the springs upon the blade.
5. An electrical switch comprising a pair of spaced terminal contact posts having spaced parallel portions mitered together at their upper ends, a pair of blades, said blades being disposed on opposite sides of the contact posts, one end of said blades being hingedly mounted upon one of said contact posts, spring washers disposed against the outwardly presented faces of the v hinged end of said blades for holding the blades with adjustable tension against the contact posts, and resilient separator means disposed between and adjacent the opposite ends of said blades for moving said blades simultaneously into and out of contact with the other contact posts.
EOLA A. LINDAE, Admintstratrix de bom's non of William H. Linda, Deceased.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Crabbs Mar. 28, 1944
US745196A 1946-08-22 1947-05-01 Switch Expired - Lifetime US2546366A (en)

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2784282A (en) * 1956-02-21 1957-03-05 Allis Chalmers Mfg Co Hinged electrical connection
US2894101A (en) * 1958-01-20 1959-07-07 S & C Electric Co Switch contact construction
US2962573A (en) * 1958-10-01 1960-11-29 Gen Electric Electric circuit interrupter
US3033964A (en) * 1958-10-01 1962-05-08 Gen Electric Electric circuit interrupter
US3183335A (en) * 1962-03-23 1965-05-11 Albert & J M Anderson Mfg Co High pressure contact switch with rotatable locking means
US3240911A (en) * 1962-05-18 1966-03-15 Westinghouse Electric Corp Electric knife switches with simplified contact pressure adjustament
US3356815A (en) * 1962-05-18 1967-12-05 Westinghouse Electric Corp Electric knife switches with simplified contact pressure adjustments
US3361880A (en) * 1966-08-19 1968-01-02 Marvin F. Symes High voltage air break switch
US3458679A (en) * 1966-09-02 1969-07-29 Robertshaw Controls Co Plug-in receptacle for a circuit selector switch
US6271489B1 (en) * 1999-12-31 2001-08-07 Square D Company Cam-lock enhanced pressure switch contacts
EP1244123A1 (en) * 2001-03-23 2002-09-25 Schneider Electric Industries SAS Device for assuring the passage of an electric current between articulated conductive arms

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US670145A (en) * 1900-06-07 1901-03-19 Bossert Electric Construction Company Electric switch.
US1192035A (en) * 1915-01-13 1916-07-25 F P Dodge Electric switch.
US1903643A (en) * 1931-04-23 1933-04-11 Railway & Industrial Eng Co Electric switch
US1935516A (en) * 1930-04-15 1933-11-14 Railway & Industrial Eng Co Switch contact and method of making the same
US1979097A (en) * 1930-05-31 1934-10-30 Champion Switch Company Lock switch
US2063954A (en) * 1930-04-19 1936-12-15 Schweitzer & Conrad Inc Switch
US2303914A (en) * 1939-09-09 1942-12-01 Westinghouse Electric & Mfg Co Circuit interrupter
US2345034A (en) * 1939-10-20 1944-03-28 Westinghouse Electric & Mfg Co Circuit interrupter

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US670145A (en) * 1900-06-07 1901-03-19 Bossert Electric Construction Company Electric switch.
US1192035A (en) * 1915-01-13 1916-07-25 F P Dodge Electric switch.
US1935516A (en) * 1930-04-15 1933-11-14 Railway & Industrial Eng Co Switch contact and method of making the same
US2063954A (en) * 1930-04-19 1936-12-15 Schweitzer & Conrad Inc Switch
US1979097A (en) * 1930-05-31 1934-10-30 Champion Switch Company Lock switch
US1903643A (en) * 1931-04-23 1933-04-11 Railway & Industrial Eng Co Electric switch
US2303914A (en) * 1939-09-09 1942-12-01 Westinghouse Electric & Mfg Co Circuit interrupter
US2345034A (en) * 1939-10-20 1944-03-28 Westinghouse Electric & Mfg Co Circuit interrupter

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2784282A (en) * 1956-02-21 1957-03-05 Allis Chalmers Mfg Co Hinged electrical connection
US2894101A (en) * 1958-01-20 1959-07-07 S & C Electric Co Switch contact construction
US2962573A (en) * 1958-10-01 1960-11-29 Gen Electric Electric circuit interrupter
US3033964A (en) * 1958-10-01 1962-05-08 Gen Electric Electric circuit interrupter
US3183335A (en) * 1962-03-23 1965-05-11 Albert & J M Anderson Mfg Co High pressure contact switch with rotatable locking means
US3240911A (en) * 1962-05-18 1966-03-15 Westinghouse Electric Corp Electric knife switches with simplified contact pressure adjustament
US3356815A (en) * 1962-05-18 1967-12-05 Westinghouse Electric Corp Electric knife switches with simplified contact pressure adjustments
US3361880A (en) * 1966-08-19 1968-01-02 Marvin F. Symes High voltage air break switch
US3458679A (en) * 1966-09-02 1969-07-29 Robertshaw Controls Co Plug-in receptacle for a circuit selector switch
US6271489B1 (en) * 1999-12-31 2001-08-07 Square D Company Cam-lock enhanced pressure switch contacts
EP1244123A1 (en) * 2001-03-23 2002-09-25 Schneider Electric Industries SAS Device for assuring the passage of an electric current between articulated conductive arms
FR2822588A1 (en) * 2001-03-23 2002-09-27 Schneider Electric Ind Sa DEVICE FOR PASSING AN ELECTRIC CURRENT BETWEEN ARTICULATED CONDUCTIVE ARMS

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