US2367391A - Electrical switch - Google Patents

Description

Jan. 16, 1945. c. A. FOX

ELECTRICAL SWITCH Filed March 8, 1 945 2 Sheets-Sheet' 2 l /YT B CHARLES AD/N Fox A 7'7'OENEY Patented Jan. 16 1945 ELECTRICAL SWITCH Charles Adin Fox, 0'akland""Villa'ge,fMo 'assignor 'Tt'o James R. Kearney'cjorn ration,- St. "Louis,

-Mo., ac'orp'oration of Missouri *Application March 8, l94{-,-,?-Serialv No.-'.4'T8 ;;3 37

8Claims.

This invention relates genera1ly to x'electric'al switches "and more specifically to. electrical switches .of the manually operated, adisconnect I type, the predominanttobjectofzthe invention being to provide an electrical 1'sWit0h "of this type which-isof vsuch improved constructioniand arrangement that the-mechanical structure oftthe switch is simplified and improvedtand which, .because .of its ,improved'icoristruction, 'iscapable of r performing :i-tS intended: function in ;a n :improved andthighly eflicientmanner;

Prior to ..this invention :many :disconnect switches. of the general type to which the present invention. relates, included in their mechanical structures r contacts which were made up. largely of castings, :and the i presence 1 of these meetings added :to the weight and complexity ylof .the switches referred to "and increased the icostmf manufacture thereof because of the initial cost of the castings and'izthewexpense incident toma- ,chining and otherwisepreparing said castingsfor quired in providing the contacts of earlier switchesof the general typeto-whichthe ;p resent invention relates and doing away withthe disadvantages attached to the use ofisuch castings. I I 1 v 1 Fig. 1 is asideelevationof the improved switch, 7 a portion .ofthe blade thereof being shown .in

section.

I ..-havingfixed: thereto a! pair of;spaced,outstand- 'ingfl insulators i2 =-and of .suitable construction, Theinsul-atorsizeand 3 may z'beesecured -.to the supportinglmember ".l .ain various ways, one .--such being -to provide seach.-.-insulator- 'with -:a1fixed1y attached xend,.member :4 from which a :screwthreaded @shank s5 rextends, :said': shankqbeinglpro- :jeoted through an :opening .-.B .(Eig. .-3) formed through. theiforwardwall ofthe supportingmemher :1 iandihavingt-arnutlI:mounted;thereonzwhich secures rtherend :membersand: insulator .-.assembl-y to ithe zsupporting member. (The eopenings -:6 formedsin the I forward walllof tthe -.su'pporting member ll through 'whicht-theu-screw threaded shanks =-.5-;ex tend, sare'ipreferably --elon-gated-.ve1ttically and extensions 8,;iormed onrthe-eendtmembars 4 of :thednsulatorsi Land 3, proj ect. into. said openings -:so as -,to ;ipreventrrotation of ithe zinsulators about (the axes -.of the. screwthreaded shanksr5 of said insulators.

v Secured -to1-the:insulator s3 is the. lower contact .9 rofithevswitch A, andksecured to'the insulator 211s: the upper-contact lfl-of theswitch. The .low-- er contact '9 1 includes as! a, part thereof the contact mart I I which .is .shown to good. advantage in-zFigs. .1,'2,Candi-said contact .part being formed whom a length.of-s.flat-metal, or other suitable "Fi .3 isra'frontelevation of. the switchshown l in Fig. l

' Fig. .3 is aplan viewof the-switch illustrated in Figs. 1* and2, a portion ofthe 'supportingsmemberof the-switch'being shown in section.

Fig; 4 is a fragmentary, horizontalsection taken on line-44. ofFig, 2-and looking inzthedirection 1 indicated by the/arrows. Y s

Fig. 5:.isa fragmentary, rear elevation illustrating' one oftheconnectors employedv for. connectgenerally. The switch A, as .illustrated in the "drawings, includesa supporting member l which, as shown to the best: advantage Lin-Fig. 3,:may be: of: channelifo'rmation, ssaidrsupporting. member material,thatis of considerablecheightasshown I tops and bottoms by wall portions ofssaidnotehes \(see Fig. 1) {The :spaced arms I l.c of the-contact,pa rt I. I are provided :withalined apertures r i,3 formed =therethrough which. serve a ,purpose to be. hereinafter set forth.

..The lower contact 9' .includesJalso .a -member L4,? insthe. formsofa .U -.shaped length. of.rod.- material, whichncontacts with an endmember 4.5

joined at their-low erends" byoa :bridge :portionf (see Fig. .2); Q'Arrangedsin contact (with: forward :por- -.-ti'ons'tof thespaced, werticalportions; of the "memher I4 is a plurality of contact elements I6, each of which is formed of resilient rod material and is shaped in plan as shown in Fig. 4. In other words, each of the contact elements I6 includes a rear portion I6a which is disposed horizontally and portions of which contact with the spaced, vertical portions of the member I4, opposed and slightly convergent portions I6b which extend forwardly from the opposite ends of said rear portion Mia, and rounded forward portions I6c at the forward ends of said portions ISb which are provided with parallel, rearwardly extended and spaced apart extensions I6d.

As is shown to good advantage in Figs. 1 and 2, the contact elements I6 are arranged in pairs, there being an upper pair and a lower pair of said contact elements and these pairs of contact elements are spaced apart vertically. Also, the extensions Hid of the respective contact elements I8 are spaced inwardly from the convergent portions IBb 'of the corresponding contact elements, as shown in Fig. 4, and the forward portions of the spaced arms IIc of the contact part II are disposed between the extensions Mid and the convergent portions I 6b of said contact elements, with the rounded portions I60 of said contact elements located in the notches I2 of said spaced arms of said contact part II. Because of this arrangement the upper pair of contact elements I6 and the lower pair of contact elements I6 are respectively prevented from moving upwardly and downwardly to an excessive degree at their forward ends, inasmuch as the upper and lower walls of the notches I2 of the spaced arms of the contact part II will arrest such movement before it becomes excessive.

Formin a part of the lower contact 9 of the switch A is a vertically disposed member H which is preferably of channel formation, as shown in Fig. 4. The channel member I1 is interposed between the base portion I Ia of the contact part 'II andthe rear portions I60, of the contact elements I6, said base Ila of the contact part H contacting with the forward wall of the channel member II whil the rear edges of the spaced side walls of the channel member contact with the rear portions of the contact elements I6. It will be noted by referring to Fig. 4 that the spacing of the spaced, vertical portions of the U-shaped member I4 is greater than th width of the channel member I1, and as a result of this situation the points at which the rear edges of the spaced Walls of said channel member contact with the rear portions of the contact elements I6 are located inwardly of the points where said rear portions of said contact elements I6 contact with said spaced, vertical portions of said U-shaped member I4. This arrangement is important for a reason to be hereinafter referred to.

In order to secure the various parts of the lower contact 9 in an assembled condition to the insulator 3, the end member I of said insulator 3 has fixed thereto and extended outwardly therefrom a screwthreaded shank I8. This shank passes between the spaced, vertical portions of the U-shaped member I4, between the rear portions of the vertically spaced pairs of contact elements I6, and said shank extends through an opening I'Ia of the channel member l1 and through the opening I lb formed through the base of the contact part I I. Mounted on the outer portion of the screwthreaded shank I8 is a nut I5 contact tosecurely fix the lower contact to the insulator 3. In this connection it is pointed out that when the nut I9 is drawn up hard on the screwthreaded shank I8 the rear portions of the contact elements I6 are bowed rearwardly slight- 1y between the locations of the spaced vertical portions of the U-shaped member I4. This produces spring contact between said rear portions of said contact elements l6 and said spaced vertical portions of the U-shaped member I4 which will maintain close contact between said portions even though the nut I9 should become unintendedly loosened slightly. Additionally, the action of drawing the nut I9 up tight on the screwthreaded shank I8 will produce an embedding action, where the rear portions of the contact elements I6 contact with the spaced, vertical portions of the U-shaped member I4, with the result that these portions are interlocked to further improve the attachment of said parts and the securement of the lower contact to the insulator 3.

The switch A includes, also, a switch blade 2i which preferably, though not necessarily, is in the form of a tube formed from electrical conducting material. Adjacent to its lower end the switch blade2l is provided with opposed apertures in which is supported a transversely extended pin 22, said pin being of such length that it extends outwardly beyond opposite sides of the switch blade to provide opposed trunnions that are mounted for rotation in the openings I3 formed in the spaced arms lie of the contact part II. This arrangement provides for pivotal support of the switch blade relative to the lower contact in order that its upper portion may be swung into and out of closed-switch position with respect to the upper contact. III of the switch. The pin 22 may be secured to the switch blade 2I in various ways, one such being to provide the pin with slightly raised, knurled portions 22' and drive these knurled portions into the walls of the alined apertures of the switch blade. According to this arrangement, the leading knurled portion of the pin, as said pin is passed through the switch blade is of slightly less height than the trailing knurled portion of the pin in order that it will pass through the first opening of the switch blade through which the leading portion of the pin passes. The switch blade 2| is provided with a pin 23 which serves to expedite the action of engaging a switch stick with the switch blade when said switch blade is to be moved to the closedswitch or open-switch positions. The pin 23 may be secured to the switch blade in the same manner in which the pin 22 is secured thereto, as described above.

The upper contact III of the switch A includes a member 24 which is shaped as shown to good advantage in Figs. 1 and 3; The member 24 is formed from a single length of heavy wire material or rod material and it includes spaced; vertical portions 25 which are arranged in engagement with the outer face of an end member 28 thatis suitably fixed to the upper insulator 2. Extended forwardly from the lower ends of the vertical portions 25 of the member 24 is a pair of spaced portions 21 which'are joined at their forward ends by a portion 28 which, as shown in Fig. 3, is preferably bowed slightly in a rearward direction. The portion 28 serves as a stop to limit rearward movement of the upper portion of the switch blade when said switch blade is moved into contact with the upper contact ID as will be presently described herein.

The upper contact II) includes also a plurality [interposed between said ;rear portions 30 of the contact elementsZBandthe forward face of the.

end member'ifi Of'thGTHPIJBIiIISUIatOI 2.

In order .tosecure the/member 24 and the elements29-of the upper contact Into the insulator 2 a member 33 lis' provided which resembles the member H :of the lower 'contact 9, in thatsaid member'is preferably of channel formation and 14a! lmOllllted ::'on the :screwthreaded part .of :the shankjportion of the clamping element of each connector which is adapted to engage the .outer face of the associated member l'l or 33. 1' The spaced sidewalls of the body portion of each connector are provided with alined conductor seats 42 whichere'adapted to receive a conduc-- tor engaged by the connector.

When a conductor is to be engaged byyone of the connectors 36 the nut ll thereof is unscrewed topermitthe clamping element 38 to move outwardly relative to the body portion 3! a sufiicient distance, to allow the conductor to be passed through the eye, of said clamping member and between the inner wall thereof andthe conductorseats 42. The .nut ll is then tightened to draw the eye portion of the clamping element 38 is'provided withan apertureformed through its forward wallthrough which is extendeda screwthreade'd shank 34 that is fixed .to and extends forwardly from the end .member 26 of the insulator 2. the member 33 contact with'the rear portions .39

of the contact elements .29, as shown in Fig. 3, t and a nut 35 is mounted on the screwthreaded shank 34 which may be drawn upon said screwthreaded shank to force the member 33, rearwardly and thereby force the ,rear portions 30 of the contact elements 29 .into close contact with the vertical portions of the member 24 and in turn forcesaid vertical portions 25 into close contact with the forward face of the end member 23 of the .insulator 2. As in the case of the lower contact 9, as-previously explained, the action of drawing up the nut 35 on the screwthreaded shank34 of the upper contact, bows the rear portions of the contact ele- The rear edges'of the sidewalls lofinwardly of the body portion 3? so as to securely clamp the conductor between the inner wall of theeye portion of the'clamping element and the conductor seats 42 of the opposed walls of said ments 29 slightlyin'a rearward direction with l the result that spring contact .is produced between the resilient rear portions of the contact elements 29 and the vertical portions '25 of the member 24, and-as a result 'ofthis spring contact close contact between said parts will be maintained even though the nut 35 becomes unintendedly loosened slightly. Also, an interlocking action is obtained between the rear portions 3!) of the contact elements 39 and the vertical portions 25 of the member 24,- due to said portions being embedded in each other'at the point where they contact, because of the clamping force exerted by the nut 35.

The members 33 .and I1 constitute the incoming and outgoing terminals of the switch A to which theincoming and outgoing electrical conductors Ca and :Cb are connected, and each of said members has associated therewith a. connector 36, said connectors being of like construce tion and arrangement.

,screwthreaded' at its outer end portion, and an eye portion at theopposite end of saiclshank portion. The shank portion 39 of the clamping element 38 extends through an opening formed ,through the portion'of the body-portion 31 which produces the ibase'thereof and throughan alined opening. formed through the forward wall of the associated membenlfl c1733, there being anut Each connector 36 ineludes a -U-shaped body portion-3l which is of bodyportion-3'l'. In addition to clamping the conductor as described, the action of tightening the nut 41 serves to securely clamp the body portion of the connector to the associated member l'l or 33, as the inward movement of the clamp-. ing element transmits movement through the clamped conductor to the body portion 3'!- which [forces the base of said body portion into close contact with the associated member whereby the forward wall of said associated member is firmly clamped between saidbase of said body portion :and the nut 4|. Conductors may be clampedby the connectors 36 when said conductors extend longitudinally of the associated members I! or .33, as is shown in Fig. 1 and by full lines in Fig. 7. Also, the connector may be shifted about the axis of the shank portion of its clamping element onequarter of a revolution to bring the connectorto a position relative to the associated member I! .or 33 where a conductor which extends transversely of said associated member maybe engaged thereby, as shown by dotted-lines in Fig. 7.

In the use of the improved switch disclosed hereinthe switch blade 2| maybe moved into or out of engagement with the upper contact :10 p

by engaging the switch blade with a suitable switch stick at the location of the pin 23 ,and

moving the-switch blade to the desired position. It is to be noted that when the switch blade is in the closed switch position the opposite end portions of said switch blade are closely engaged by the portions led of the resilient contact elements I6 of the lower contact?! and by the portions 32 of the resilient contact elements 29 of the upper contact it toprovide flexible, floating,

point pressure contact between said contact elements and said switch blade to afford the .de-

' sired and required goodelectrical contact between said parts. Also,-because the. contact ele-\ ments I6 of the lower contact 9 are arranged in spaced pairs, the switch blade is arrested, and may be retained, in a horizontal position when said switch blade is in the open switch position, this result being brought about because the portions l6d of the resilient contact elements l6 will move'inwardly, when the switch blade is in the horizontal position, to engage receding portions of thesurface of the switch blade located above and below the point of pivotal connection of the switchblade. Additionally, because of the fact that portions of the contact elements I6 of the lower contact are disposed in the notches [2 of the contact part H of saidlower contact, undue spreading ofthe ,outer endportions of the pairs of contact elements is prevented when the switch blade is in the horizontal position, or at any other time.

I claim:

l. A contact for an electrical switch having supporting means for supporting the contact, comprising a member having spaced extensions which contact with a face of said supporting means, a plurality of contact elements formed from lengths of resilient material which are provided with portions that contact with the spaced extensions of said member, and means for securing said member having spaced extensions and said plurality of contact elements to said supporting means, said securing means comprising a member which contacts with said portions of said plurality of contact elements at points there- .of located inwardly of said spaced extensions of the first-mentioned member, and means for moving the second-mentioned member so as to force said portions of said plurality of contact elements into close contact with said spaced extensions of said first-mentioned member and for forcing said spaced extensionsof said first-mentioned member against the face of the supporting means with which they contact.

2. A contact for an electrical switch having supporting means for supporting the contact, comprising a member having spaced extensions which contact with a face of said supporting means, a plurality of contact elements formed from lengths of resilient material which are provided with portions that contact with the spaced extensions of said member, and meansfor securing said member having spaced extensions and said plurality of contact elements to said supporting means, said securing means comprising a member which contacts with said portions of said plurality of contact elements at points thereof located inwardly of said spaced extensions of the first-mentioned member, and means comprising a screwthreaded shank supported by said supporting means and a nut mounted on said screwthreaded shank for moving the secondmentioned member so as to force said portions of said plurality of contact elements into close contact with said spaced extensions of said firstmentioned member and for forcing said spaced extensions of said first-mentioned member against the face of the supporting means with which they contact.

3. A contact for an electrical switch having supporting means for supporting the contact, comprising a member having spaced extensions which contact with a face of said supporting means, a plurality of contact elements formed from lengths of resilient material which are provided with portions that contact with the spaced extensions of said member, and means for securing said member having spaced extensions and said plurality of contact elements to said supporting means, said securing means comprising a channel member which contacts with said portions of said plurality of contact elements at points thereof located inwardly of said spaced extensions of the first-mentioned member, and means for moving said channel member so as to force said portions of said plurality of contact elements into close contact with said spaced extensions of said first-mentioned member and for forcing said spaced extensions of said first-men tioned member against the face of the supporting means with which they contact.

4. An electrical switch comprising spaced contacts, supporting means for said spaced contacts,

Iii

I'll

and a switch blade having pivot means associated therewith providing for pivotal attachment of said switch blade to one of said spaced contacts at a point adjacent to an end of the switch blade so that the opposite end portion of the switch lblade may move into and out of electrical contact with the other of said spaced contacts, said contact to which the switch blade is pivotally attached including elongated spaced arms which are supported by and extend from the supporting means for the contact, a portion of the switch blade being disposed between saidspaced arms in spaced relation with respect thereto and said spaced arms being provided with apertures which receive portions of said pivot means, and a plurality of contact elements formed from lengths of resilient material, said Contact elements being supported by the supporting means for the contact and being composed of opposed portions extended forwardly from said contact-supporting means in outwardly spaced relation with respect to the outer faces of said spaced arms and with respect to the switch blade, and inwardly and rearwardly bent forward portions disposed in inwardly spaced relation with respect to the inner faces of said spaced arms and which contact with opposite outer portions of said switch blade to make good electrical contact therewith, forward portions of said contact elements being arranged in embracing relation with respect to forward portions of said spaced arms.

5. An electrical switch comprising spaced contacts, supporting means for said spaced contacts, and a switch blade having pivot means associated therewith providing for pivotal attachment of said switch blade to one of said spaced contacts at a point adjacent to an end of the switch blade so that the opopsite end portion of the switch blade may move into and out of electrical contact with the other of said spaced contacts, said contact to which the switch blade is pivotally attached including a member supported by the supporting means for the contact which is provided with elongated spaced arms that project from said contact-supporting means, a portion of the switch blade being disposed between said spaced arms in spaced relation with respect thereto and said spaced arms being provided with apertures which receive portions of said pivot means, and a plurality of contact elements formed from lengths of resilient material, said contact elements being supported by the supporting means for the contact and being composed of opposed portions extended forwardly from said contact-supporting means in outwardly spaced relation with respect to the outer faces of said spaced arms and with respect to the switch blade, and inwardly and rearwardly bent forward portions disposed in inwardly spaced relation with respect to the inner faces of said spaced arms and which contact with opposite outer portions of said switch blade to make good electrical contact therewith, forward portions of said contact elements being arranged in embracing relation with respect to forward portions of said spaced arms.

6. An electrical switch comprising spaced contacts, supporting means for said spaced contacts, and a switch blade having pivot means associated therewith providing for pivotal attachment of said switch blade to one of said spaced contacts at a point adjacent to an end of the switch blade so that the opposite end portion of the switch blade may move into and out of electrical contact with the other of said spaced contacts, said by the supporting means for the contact and being composed of opposed portions extended forwardly fromsaid contact-supporting means in outwardly spaced relation with respect to the outer faces of said spaced arms and with respect vto the switch blade, and inwardly and rearwardly bent forward portions disposed in inwardly spaced relation with respect to the inner faces of said spaced arms and which contact with opposite outer portions of said switch blade to make good electrical contact therewith, forward portions of said contact elements being arranged in embracing relation with respect to forward portions of said spaced arms.

7. An electrical switch comprising spaced conof said spaced arms and which contact with op- .posite outer portions of said switch blade to make good electrical contact therewith, forward portions of said contact elements being arranged in embracing relation with respect to forward portions of said spaced arms.

8. An electrical switch comprising spaced contacts, supporting means for said spaced contacts,

. and a switch blade having pivot means associated tacts, supporting means for said spaced contacts,

elongated spaced arms that project from said contact-supporting means, a portion of the switch blade being disposed between said spaced arms in spaced relation with respect thereto and said spaced arms being provided with apertures which receive portions of said pivot means, and a plurality of contact elements formed from lengths of resilient material, said contact elements being supported by the supporting means for the contact and being composed of opposed portions extended forwardly from said contact-supporting means at opposite sides of said pivot means and disposed.

therewith providing for pivotal attachment of said switch blade to one of said spaced'contacts at a point adjacent to an end of the switch blade so that the opposite end portion of the switch blade may move into and out of electrical contact with the other of said spaced contacts, said contact to which the switch blade is pivotally attached including a member supported by the supporting means for the contact which is provided with elongated spaced arms that project from said contact-supporting means, a portion of the switch blade being disposed between said spaced arms in spaced relation with respect theretoand said spaced arms being provided with apertures which receive portions of said pivot means, and a plurality of contact elements formed from lengths of resilient material, said contact elements being supported by the supporting means for the contact and being composed of opposed portions extended forwardly from said contact supporting means in outwardly spaced relation with respect to the outer faces'of. said spaced arms and with respect to the switch blade, and inwardly and rearwardly bent forward portions disposed in inwardly spaced relation with respect to the inner faces of said spaced arms and which contact with opposite outer portions Of said switch blade to make good electrical contact therewith,'forward portions of said contact elements being arranged in embracing relation with respect to forward portions of said spaced arms, and said spaced arms being provided with notches formed in the forward portions thereof in which the forward portions of the contact elements are CHARLES ADIN FOX.

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