US2566917A - High-voltage electric switch - Google Patents

Description

J. G. ARMSTRONG HIGH-VOLTAGE ELECTRIC SWITCH 2 Sheets-Sheet INVENTOR; weed @ffm-6521 ci? BY Sept. 4, 1951 Filed March 16, 1950 Sept. 4, 1951 J. G. ARMSTRONG 2,566,917

HIGH-VOLTAGE ELECTRIC SWITCH INVEN TOR.

Patented Sept. 4, 1951 HIGH-VOLTAGE ELECTRIC SWITCH James G. Armstrong, Centralia, Mo., assignor `to A. B. Chance Company, Centralia, Mo.,

poration of Missouri Application March 16, 1950, Serial No. 150,041

(Cl. ZOO-162) 4 Claims.

The present invention relates to high voltage electrical switches, and is particularly concerned with insulator supported electrical switches which are adapted to be latched in the closed position, and manipulated to open or closed position by a clamp stick.

One of the objects of the invention is the provision of an improved switch of the class described, the blade structure of which may be manufactured more cheaply than the devices of the prior art, but at the same time presents a more rigid and durable structure by virtue of its improved construction.

Another object of the invention is the provision of an improved switch, the switch arm of which is constructed out of tubular metal members, the ends of which have been flattened to secure a maximum electrical contact withthe terminals, and the intermediate parts of which are still in a tubular shape and arranged in the manner of a truss for maximum lateral rigidity.

Another object of the invention is the provision of a switch of the class described which is automatically latched when it moves to the closed position, but which may be unlatched by apply- `ing a clamp stick to the operating ring and moving the ring in such a direction as to open the switch, and which is also adapted to be supported in open position, where it is stopped automatically -by means of suitable stop elements carried by the `switch arm and the pivot terminal.

Another object of the invention is the provision of an improved switch of the class described, which is durable, which has a minimum contact resistance, which may be manufactured economically, which is sturdy, and adapted to be used 4for a long period of `time without necessity for repair or replacement of any of ,its parts.

lOther objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar .characters of reference indicate similar lparts throughout the several views.

Referring to the drawings, of which there are two sheets,

Fig. 1 is a fragmentary side elevational view of .a high voltage switch `embodying my invention;

Fig. 2 isa top plan view omitting the electric insulators;

Fig. 3 is a fragmentary side elevational view in partial `section on the plane of the line 3-3 of Fig. 2, looking in the direction of the arrows, :showing the latching mechanism and the fixed terminal -of lthe switch;

Fig. -4 is a fragmentary sectional view, taken 2A on the plane of the line 4 4 of Fig. 3, looking in the direction of the arrows, and showing the details of `construction at the latching end of the switch arm; I

Fig. 5 is a fragmentary elevational view in partial section, shown on the plane of the line 5-.5 of Fig. 3, lookingin the direction of the arrows.

The present switch I0 is preferably insulator supported and may be mounted upon a pair of insulators I I and l2, which are carried by a metal frame member, such as a U-shaped channel (not shown. The insulators are of the type having metal members attached to their upper ends, with threaded bores for receiving the screw bolts which secure the terminals to the insulators, such as, for example, the screw bolts I3 at the right or pivot terminal and thescrew bolts I4 at the left or latching terminal.

The pivoting terminal I5 may consist of a cast metal member provided with a fiat base plate I6 of substantially the same shape as the top of the insulator and provided with bores for passing the screw bolts I'3, by means fof which it is secured to `the insulator. I

The base plate I5 hasan integral rearward extension Il, which is provided with four threaded bores I8 for receiving the connector screw bolts I'il, by means of which a connector piate 2U is clamped to the extension I'l.V The line conductors are clamped in grooves in the plates Il and 20 by the screw bolts I9 threadedinto bores I8.

The terminal base I6 supports a pair of upwardly extendingpivot colums 2|, 2|, each of which has a through 'bore 22 Y,for passing the screwbolts .23. The screw bolts .23 also pass through bores 24 inthe blades 25 and 26 0f the ,Switch arm 21.

Spring washers2B are included on ea-ch .of .the screw bolts 23 ,between the head .and the blades `2li and 26; `and the spring washers are brought inifo'resilient` and clamping engagement with the blades ,by tightening the nuts` 29.

Each .of .the pivot columns 2l has anouter plane surface 30 for engagement with the blades 25, 216. The blades 25er-1d L26 are preferably made out 'of `.copper tubes by flattening the end portions 3l., 32 adjacent the pivot terminal and by iiattening .the other end portions 33, 34 adjacent the fixed terminal 35.

Between the attened portions at 3l, 32 and 33, r3'II there are theintermediate tubular por- .tions 36, 3J, which `merge into Vthe flattened por; tions at each lend by being gradually tapered i'n thickness and flattened The attened portions 33, 34 are .s0 bent that they fare parallel when 3 spaced sufficiently to engage the upwardly extending legs 38, 39 of the xed terminal 35.

The other flattened ends 3| 32 are also bent so that they extend parallel when they engage the outer surfaces 3,0 of the terminal columns 2|, which are spaced from each other as much as is permitted by the diameter of the base plate I6 at the pivot terminal. Thus the blades 25, 26 of the switch arm 21 form a triangle and assume a truss-like shape, in which the tubular portions are placed, one under tension, and the other under compression by any lateral force, which tends to bend the switch arm sidewise.

The xed terminal columns 2| may each be provided with a lower thicker portion 40, forming a horizontal stop shoulder 4|, which is located below each blade 3|, 32. The attened end portions 3|, 32 of each blade have the straight end surfaces 42, which are located to come into engagement with the shoulder 4| when the blade reaches the dotted line open position indicated at 43; and the lower rear corner 44v of each flattened blade portion 3|, 32 is beveled closer to the spring washer 28 than the location of the end 42, to clear the stop surface 4| as the blade pivots upward.

` Each pivot column 2| may be provided with an upward extension 45 curved on the back side, but having an abrupt shoulder 46 on the front side. This shoulder 46 is adapted to engage a transverse pin 41, which passes through apertures in each of the attened blade portions 3|, 32, and is secured at each end 48 by a through cotter pin.

The pin 41 engages the stop surface 46 at the same time that the stop surface 42 engages stop 4|. The switches are customarily mounted in vertical position, with the xed contact uppermost and the pivot column lowermost. Thus the switch is held in open position by gravity.

At its other end the flattened portions 33, 34 are secured together in parallel position by a plurality of through rivets 49, which also pass through a spacer block 50 engaging the inside of the blade portions 33, 34. At its extreme end the flattened portions 33, 34 are secured together in parallel position by engaging a spacer block 5| (Fig. 4), which has a pair of through rivets 52 riveted over at both ends and clamping the blade portions to the block.

The spacer block 5| is provided with a round tapered socket 53 on its inner side between the blades for receiving the compression spring 54, by means of which the latches 55 are urged toward the latching position 55. The spring 54 has its other end mounted upon the cylindrical guide portion 56 of a spring supporting lever 51, which is provided with a bearing ange 58 pivotally mounted upon a pintle 59 passing through both of the depending latches 55.

Each of the latches comprises a metal member formed with a bearing portion 60 at the top and with a hook portion 6| at the bottom. The hook portion has a partially cylindrical recess 62 for `engaging a pin 63 and latching the switch in closed position.

Each hook is also beveled at 64 on its lower side toward the pin 63 so ythat when the switch is vpulled shut, the beveled portion 64 engages pin 63 to cam each latch to the open position until it passes over the pin and the pin 63 engages in the recess 62.

`The upper or bearing portion of each latch is pivotally mounted upon a bolt 65 carried by the two flattened blade portions 33, 34 in through apertures and provided with a cotter pin at its free end. The same bolt 65 pivotally mounts a ring operating member 66 between the two latches Y 55; and the ring operating member has a ilat body fitting between the latches on the bolt 65.

The ring operator 66 also has a pair of depending flanges 61, one on each side, engaging the right side of each latch 55 so that when the ring operator is moved clockwise, the flanges 61 engage the latches 55 and-move them to unlatching position against spring 54.

lThe body 68 of the ring operator '66 extends upward above the blades and is provided with a ring 69 having a-round opening 10 suitable for engagement with a clamp Vstick or a disconnect stick of the `type having a laterally extending lug and a head.

The body 68 has a laterally extending stop flange 1| on each side, which prevents the ring operator 66 from moving counterclockwise any farther than the position of Fig. 3, where this ange 1| engages the top of each blade. The flange 1| has another stop flange 12 extending upward and toward the right in Fig. 3 at an obtuse angle for thepurpose of engaging thejtop edges of the blades on each side, when the ring operator is pivoted clockwise, to bring this ange into engagement with the blades. f

The body 68 of the ring operator 66 also has a prying extension 13 located below the ange 12 and adapted to come into engagement with the flat end 14 of the terminal column 38 to pry the blades loose from the terminal 35 in the initial movement of the ring operator.

The other leg 39 of the terminal 35 may have a roundedend extending above the blades in Fig. 3. The xed terminal 35 of the switch comprises a cast metal member having a base plate 15 provided with apertures for passing the screw bolts |4, which are threaded into metal sockets that are secured in the insulator.

The base plate 15 has a similar outward extension |3 supporting clamping plates |1 and 20, which are drawn together by the threaded bolts I8. The base plate 15 supports the upwardly extending terminal columns 38 and 39, which are preferably rectangular in cross section and of suiiicient thickness to engage the inside of the flattened blade portions 33, 34 tightly.

The terminal column 38 is provided with a laterally projecting vertical flange 16, which is adapted to go between the two latches 55, and which carries the latching pin 63 that serves as a keeper and projects laterally from both sides of the iiange.

The two terminal columns 38, 39 are separated by a parallel sided slot 11 of sufficient width to receive the tubular spacer 18, which is carried'by a through bolt 19. The through bolt 19 passes through registering apertures in the flattened blade portions 33, 34, and is provided on one end with a spiral compression spring 8l] compressed between the head 8| and the blade portion 33.

A spring washer 82 is compressed between the nut 83 on the threaded end of the bolt and the blade portion 34. The spacer 18 may be slightly shorter than the thickness of the terminal columns 38, 39 so that the spring 80 and spring washer 82 press the blade portions 33, 34 into tight engagement with the terminal legs 38, 39. Y

The base plate 15 of terminal 35 is preferably provided with a verticalilange 85 (Fig. 3) having a pair of bores for'receiving the screwbolts 86 (Fig. 5), which are used with nuts to secure a U-shaped guideV member 81 to the baise.V U-shaped guide member has two upwardly extending legs 88 and a lower yoke 89, the yoke TheV being provided with apertures for receiving the tous at.

The slot between the legs l88 is `indiiated at 590-; and -i-t is `rectangular iin sha-pe and bordered by laterally projecting ilanges '91, except 'tlataft 92 the reinforcing :flanges have outwardly flaring portions 93, `forming a diverg-ing mouth, which will engage the blades vand guide them into en'- gagement with the legs 38, 39 ofthe fixed terminal 35.

The operation of lthe present switch is as follows: Assuming that "the switch Vis closed, vas shown in Fig. 1, it may be 'opened Eby applying a disconnect stick to 'the Yring '6-9 fand pushing upward. This motion will be resisted by the spring 54 because the `depending -ilange 'B1 (Fig. 3) on the operator -65 engages the latches 55 and moves them clockwise 'to fthe unlatching position off the Spin 63. When the ring 'has moved its extension 13 into engagement with the end 14 of the terminal prong `38, further movement of the operating ring 69 tends to pry the blade off the terminal 35. A

The prying movement is required `only at the beginning of the motion of the switch arm because the moving friction is much less than the static friction. The prying continues until the flanges 12 engage the upper edges of the blade portions 33, 34. Thereafter the ring operator 5t can pivot no farther on the bolt A65 in a clockwise direction; and the ring operator serves as a rigid handle for engagement with `the disconnect `stick to move the switch arm upward and to effect a disconnection at the terminal 35.

The upward motion of the switch arm `may continue until it reaches the dotted line position, shown in Fig. 1, whereupon the pin 41 en gages shoulder 46; and thejilat edge 42 engages shoulder il to prevent further opening motion of the switch ar'm.

` When the switch is to be closed, a disconnect stick may be employed again in the 59, which is pulled downward. Any lateral component of the pull exerted is resisted by the trussu like structure of the switch arm 21, the tubular portions 3S and 31 of which `are much stronger than they would be if they were `flat.

As the switch arm approaches the terminal 35,

it is guided by the U-shaped guide member 81 into engagement with the legs 38, 39. These terminal legs 38, 39 pass in between the flattened portions 33, 34; and as the latches 55 approach the pin 53, the beveled surface 64 on each latch cams the latches outward toward the left, until they pass over the pins 53 and snap into latching position. The switch is now closed and latched in closed position; and the parts are in the position of Figs. 1 and 3.

It will thus be observed that I have invented .l

an improved high voltage switch, the switch arm of which is of a structure like a truss and having two tubular side members, which are spread at one end and brought together at the other end. Flattening the tubular members at the ends gives them both an extended plane contact area for engaging the terminals, which reduces contact resistance.

The tubular members are secured together at both ends, and are resiliently clamped to the pivot terminal so that the friction is suflicient to hold the switch in open position against gravity. At the other end the terminal has a guide for guiding the switch arm into engagement with the terminal, and is provided with an automatic latch iorlll'a'tching the. `switch in `closed position `and for prying the switch to open position.

While vl have illustrated a :preferred 'em'bozdiment `of my invention, manymodincations may be made without 'departing from the spirit of the `in;- vention, and I do not wish to be limited to the precise 'details `vor construction set forth, but desire to avail myself vof vall changes within the scopelof the appended claims.

Having thus 'described my invention, what `I claim as new and `desire to secure by Letters Paitent 'of Vthe United States, is:

1. In a high voltage switch, the combination oi a support with a .pair of insulators, each 'of said insulators having a metal cap provided with threaded bores, a fixed contact terminal carried by the cap of one insulator, a pivot `terminal litting carried by the other insulator and secured thereto by threaded members, said pivot terminal having a pair of upwardly extending spaced parallel pivot columns, and a movable switch arm pivotally mounted on said columns, said switch arm .comprising a pair of blade members, the said blade `members each comprising a tubular metal member having both of its ends flattened to provide inner plane contacting surfaces, the tubular portions intermediate the ends extending di agonall'y 'outward toward the pvot terminal columns, and the flattened end portions adjacent said columns being pivotally mounted on said columns -by clamping screw bolts, 4each screw bolt having a spring washer for resiliently pressing the iiatten'ed portions against the pivot columns to reduce contact resistance, the said pivot columns being provided on their upper ends with upwardly extending shoulders, and the blades being provided with aligned apertures adjacent said col'-` umns and with a through stop pin in said apertures and located to engage said upwardly rex@r tending shoulders when the arm is opened and moved to an upwardly extending position.

2. In a high voltage switch, the combination of a support with a pair of insulators, each of said insulators having a metal ca'p provided with threaded bores, a fixed contact terminal carried by the cap 'of one insulator, a pivot terminal fitting carried by the other insulator and secured thereto by threaded members, said pivot terminal having a pair of upwardly extending spaced parallel pivot columns, and a movable switch arm pivotally mounted on said columns, said switch arm comprising a pair of blade members, the said blade members each comprising a tubular metal member having both oi its ends flattened to provide inner plane contacting surfaces, the tubular portions intermediate the ends extending diagonally outward toward the pivot terminal columns, and the flattened end portions adjacent said columns being pivotally mounted on said columns by clamping screw bolts, each screw bolt having a spring washer forresilientlypressing the flattened portions against the pivot columnsto reduce contact resistance, the said pivot columns being provided on their upper ends with upwardly extending shoulders, and the blades being provided with aligned apertures adjacent said columns and with a through stop pin in said apertures and located to engage said upwardly extending shoulders when the arm is opened and moved to an upwardly extending position, said xed contact terminal comprising a supporting base and a pair of longitudinally spaced upwardly extending prongs separated by a slot, said prongs being of slightly greater width than the spacing between 7 the adjacent attened end portions of the switch blades.

3. In a high voltage switch, the combination of a support with a pair of insulators, each of said insulators having a metal cap provided with threaded bores, a xed contact terminal carried Vby the cap of one insulator, a pivot terminal fitting carried by the other insulator and secured thereto by threaded members, said pivot terminal having a pair of upwardly extending spaced parallel pivot columns, and a movable switch arm pivotally mounted on said columns, said switch arm comprising a pairof blade members, the said blade members each comprising a tubular metal member having both of its ends flattened to provide inner plane contacting surfaces, the tubular portions intermediate the ends extending diagonally outward toward the pivot terminal colu umns, and the flattened end portions adjacent said columns being pivotally mounted on said columns by clamping screw bolts, each screw bolt having a spring washer for resiliently pressing the flattened portions against the pivot columns to reduce contact resistance, the said pivot columns being provided on their upper ends with upwardly extending shoulders, and the blades being provided with aligned apertures adjacent said columns and with a through stop pin in said apertures and located to engage said upwardly extending shoulders when the arm is opened and moved to an upwardly extending position, said fixed contact terminal comprising a supporting base and a pair of longitudinally spaced upwardly extending prongs separated by a slot, said prongs being of slightly greater width than the spacing between the adjacent attened end portions of the switch blades, the switch blades being provided with a pair of elongated attened portions arranged on opposite sides of said prongs and spaced from each other in parallel relation by a tubular spacer and a through securing member at each end of said latter flattened portions.

4. In a high voltage switch, the combination of a support with a pair of insulators, each of said insulators having aY metal cap provided with threaded bores, a fixed contact terminal carried by the cap of one insulator, a pivot terminal ntting carried by the other insulator and secured thereto by threaded members, said pivot terminal having a pair of upwardly extending spaced parallel pivot columns, and a movable switch arm pivotally mounted on said columns, said switch CJI arm comprising a pair of blade members, the said blade members each comprising a tubular metal member having both of its ends attened to provide inner plane contacting surfaces, the tubular portions intermediate the ends extending diagonally outward toward the pivot terminal columns, and the atttened end portions adjacent said columns being pivotally mounted on said columns by clamping screw bolts, each screw bolt having a spring washer for resiliently pressing the iiattened portions against the pivot columns to reduce contact resistance, the said pivot columns being provided on their upper ends with upwardly extending shoulders, and the blades being provided with aligned apertures adjacent said columns andY with a through stop pin in said apertures and located to engage said upwardly extending shoulders when the arm is opened and moved to an upwardly extending position, said xed contact terminal comprising a supporting base and a pair of longitudinally spaced upwardly extending prongs separated by a slot, said prongs being of slightly greater Width than the spacing between the adjacent flattened end portions of the switch blades, the switch blades beingv provided with a pair of elongated attened portions arranged on opposite sides of said prongs and spaced from each other in parallel relation by a tubular spacer and a through securing member at each end of said latter attened portions, and said parallel flattened portions being traversed at the slot between said prongs by a transversely extending bolt provided with a threaded securing member, and having spring means on said bolt outside of each flattened portion to press the flattened portions together against the prongs and to permit their separation suiciently to receive the prongs.

JAMES G. ARMSTRONG.

REFERENCES CITED I The following references are of record in the file of this patent:

UNITED STATES PATENTS

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