US3361880A

US3361880A - High voltage air break switch

Info

Publication number: US3361880A
Application number: US573693A
Authority: US
Inventors: Marvin F Symes
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-08-19
Filing date: 1966-08-19
Publication date: 1968-01-02
Anticipated expiration: 1985-01-02
Also published as: AU3179967A; GB1139720A; DE1690125A1; AU416626B2

Description

Jan. 2, 1968 M. F. SYMES 3,361,330

HIGH VOLTAGE AIR BREAK SWITCH Filed Aug. 19, 1966 5 Sheets-Sheet 1 IIIIHII Marvin Fsymes Q Q BY INVENTOR E: R3 @Q2% Hgeni Jan. 2, 1968 M. F. SYMES I HIGH VOLTAGE AIR BREAK SWITCH 5 Sheets-Sheet 2 Filed Aug. 19, 1966 llll R 1T i %m n [l mm e V 0% g n F. MN.

.i d? I v H m mm NM. MY vw B Jan. 2, 1968 M. F. SYMES 3,361,880

HIGH VOLTAGE AIR BREAK SWITCH Filed Aug. 19, 1966 5 Sheets-Sheet Marvin F Symes BY INVENTOR Jan. 2, 1968 M. F. SYMES HIGH VOLTAGE AIR BREAK SWITCH 5 Sheets-Sheet 4 Filed Aug. 19, 1966 Marvin F S mes BY INVENTOR v Hgeni Jan. 2, 1968 M. F. SYMES HIGH VOLTAGE AIR BREAK SWITCH 5 Sheets-Sheet 5 Filed Aug. 19, 1966 BY INVENTOR Qgeni United States Patent 3,361,880 HIGH VOLTAGE AIR BREAK SWITQH Marvin F. Symes, R0. Box 19252, Portland, Greg. 97219 Filed Aug. 19, 1966, Ser. No. 573,693 6 Claims. (Cl. 200-48) ABSTRACT OF THE DHSCLOSURE A high voltage air brake switch comprising a switch arm-supporting unit, a switch arm, a switch blade, a contact unit, and a switch arm locking means securing the base member and support member of the switch armsupporting unit together releasably against pivotal movement of the support member about the pivot means.

This invention relates to electric switches, and more particularly to a high voltage electric switch of the air break type.

It is the principal object of the present invention to provide a high voltage air break switch which offers the following advantages:

The switch involves a minimum number of basic components which are utilized to make up any one of a variety of types of air switches, such as hook-operated, single or center side break, rocker shaft and others, by use of a minimum number of simple adapter components.

The switch requires a minimum inventory of number of components, thus minimizing the cost of production and assuring ready availability of parts for replacement, repair and modification to other types of switches.

The use of a minimum number of parts correspondingly minimizes the incidence, time and cost of maintenance and repair.

The switch is capable of mounting upon standard insulators.

The switch is usable in circuits carrying a wide range of currents and voltages.

The foregoing and other objects and advantages of this invention will appear from the following detailed description, taken in connection with the accompanying drawings in which:

FIG. 1 is a side elevation of a high voltage air break switch of the hook-operated type, embodying the features of the present invention;

FIG. 2 is a plan view of the switch shown in FIG. 1;

FIG. 3 is an end elevation as viewed from the left in FIG. 1;

FIG. 4 is a fragmentary sectional view taken on the line 44 in FIG. 1;

FIG. 5 is an end elevation as viewed from the right in FIG. 1;

FIG. 6 is a fragmentary sectional view taken on the line 66 in FIG. 1;

FIG. 7 is a side elevation similar to FIG. 1 showing a high voltage air break switch of the single side break type embodying the features of the present invention;

FIG. 8 is a plan view of the switch shown in FIG. 7;

FIG. 9 is a fragmentary sectional view taken on the line 9-9 in FIG. 7; and

FIG. 10 is a side elevation similar to FIGS. 1 and 7 showing a high voltage air break switch of the rocker shaft type.

Referring first to the embodiment illustrated in FIGS. 1-6 of the drawings, there is shown for purposes of illustration a pair of spaced

electrical insulators

10, 12 of conventional construction, secured to an underlying support 14, in manner well known in the art. Mounted upon one of these insulators, the left hand insulator 10 illustrated in FIG. 1, is the switch contact unit 16 which supports the switch arm 18. On the other insulator 12 there is mounted the contact unit 20 which carries contact members adapted to releasably engage the blade 22 carried by the switch arm.

The arm-supporting contact unit 16 includes a U- shaped base member of electrically conductive material. The closed bottom end 24 is provided with a longitudinal groove adapted to seat the shank end 26 of a removable terminal connector 28. Registering openings in the shank and closed end of the base member receive therethrough a pair of spaced bolts 30 by which the assembly is secured to the insulator 10.

Overlying the upper ends of transversely spaced upstanding arms 32 of the base member is a U-shaped support member. The transversely spaced downwardly depending arms 34 of the support member overlap the upper portions of the arms 32 of the base member, and these arms are provided with aligned registering openings for the reception of the pivot bolts 36. The support member thus is pivotable on a transverse axis relation to the base member.

In the preferred embodiment illustrated (FIG. 4), a washer 38 is interposed between the

arms

32 and 34, concentric with the bolt 36. The washer is made of silver or other metal having greater electrical conductivity than the metal, forming the base and support members. The latter preferably are cast from NEMA standard contact metal. A spring Washer 40 on the bolt urges the assembly together resiliently to maintain positive contact between the arms and silver washer. By use of the silver washer the usual costly procedure of silvering the abutting surfaces of the arms is avoided.

When the switch is employed in circuits carrying currents higher than about 600 amperes, positive electrical continuity between the support member and the base member is provided by means not only of the silver washer 38 but also of the electrically conductive, flexible straps 42 secured at their opposite ends to said members by such means as the screws 44. For even higher currents, additional pairs of straps may be used.

The head end of the terminal connector 28 is provided with one or more openings 46 for the releasable attachment of a high voltage conductor, as by means of bolts.

Registering openings 48 (FIG. 1) are provided in one of the upstanding arms 32 of the base member and the associated downwardly depending arm 34 of the support member, for the removable reception of a locking bolt 50 (FIG. 7), for purposes explained more fully hereinafter.

The central portion 52 of the closed end of the support member is enlarged vertically and provided with a longitudinal bore therethrough for the reception of one end of the elongated, tubular switch arm 18. The bottom side of this enlarged portion is split longitudinally, and a pair of lugs 54 (FIG. 3) depend downwardly therefrom on opposite sides of the split. The lugs are provided with aligned openings, one of which is threaded for the reception of the clamping screw 56. Thus, the switch arm is secured removably at one end to the support member frictionally by the clamping action of the screw. Axial rotation of the switch arm relative to the support member is prevented by means of the set screw 58 anchored in a threaded opening in the support member and penetrating the surface of the switch arm.

The end of the switch arm opposite its attachment to the support member removably mounts the contact blade 22. In the embodiment illustrated, the blade is provided with a shank extension 60 which is received freely in the open end of the tubular arm and is secured removably thereto by means of a set screw 62 which is received in a threaded opening in the arm and enters a registering socket in the shank extension. The plane of the blade parallel to the opposed fiat sides thereof thus is oriented parallel to the plane of pivotal movement of the arm about the pivot bolts 36.

The switch contact unit 21), mounted on the right hand insulator 12 in FIG. 1, includes a base member which comprises a bottom plate 64 and a central upstanding pedestal 68 integral therewith. The bottom plate is provided with an integral longitudinal extension provided with a pair of openings 70 for the reception of bolts by which to secure the other electrical conductor of the electric circuit which is desired to be switched.

The upstanding pedestal 66 has a horizontal cross sectionalshape of an I-beam. The laterally spaced flanges of the pedestal define between them opposed guide channels in which are freely confined the lower portions of a pair of upstanding electrical contact members 72, 7d. Transverse openings in the lower ends of these contact members register with an opening in the pedestal, for the removable reception of the connecting bolt 76.

In the preferred embodiment illustrated (FIG. 6) the opposite ends of the opening in the pedestal are countersunk to form sockets for the ball projections 78 on the contact members concentric with the openings for the bolt 76. There is thus provided a ball and socket joint for each contact member, permitting the latter to move laterally inward and outward relative to the pedestal. The connecting bolt is secured loosely to accommodate this motion.

Upwardly from the transverse openings for the bolt 76 there are additional transversely openings in the contact members and pedestal. These aligned openings freely receive the pressure-adjusting bolt 80. A pair of springs 32 encircle this bolt, one adjacent each end for resilient bearing against each of the contact members. Tightening or loosening of the nut 84 thus varies the pressure of the springs against the contact members and hence the contact pressure of the members against the switch blade 22.

The pressure adjusting bolt also serves to connect one of the ends of at least one pair of flexible electrically conductive straps 86 to the contact members. The opposite ends of the straps are secured to the bottom plate 64 of the contact unit, by means of the screws 38, whereby to provide positive electrical continuity between the plate and contact members. The screws also serve to secure the bottom plate, and hence the contact unit to the insulator 12.

In the closed position of the hook-operated switch, the blade 22 is interposed between the

contact members

72, 74 which are caused to bear firmly against opposite sides of the blade with a desired pressure, obtained by appropriate adjustment of the bolt nut 84. The blade is secured in this closed position by means of the locking member 90 removably secured one to each of the outer, diverging end portions of the contact members, as by means of the screws 92. The lower end of each locking member projects inward beyond the blade-contacting surface of the contact member, overlying the blade when in closed position.

Means is provided for releasing the blade from its locked position. The illustrated means for this purpose is a conventional hook member comprising a cam member 94 mounted pivotally on the blade by means of the removable pivot bolt 96. Integral with the cam member is an enlarged ring 98 adapted to be engaged by a conventional pole hook.

The cam member 94 is positioned for pivotal movement about the bolt between a retracted position outward from the diverging locking members Qd, and an operative position inward between the locking members and in abutment with the upper surface of the blade 22. The cam member has a width at least equal to that of the blade. Accordingly, when in operative position the cam member forces the locking members and contact members apart sufliciently to permit the blade to be extracted from under the locking members, by an outward pull on the ring.

The current and voltage switching capacity of the switch may be increased by the addition of a second pair of contact members. This addition is provided for in the embodiment illustrated in FIG. 1 by the second upstanding pedestal 66. This pedestal is joined integrally With the main pedestal, utilizing one of the lateral flanges of the latter in association with the spaced flange of the second pedestal to provide between them a second pair of opposed guide channels for seating the second pair of contact members. A transverse, countersunk opening through the second pedestal provides the socket mounting for the second pair of contacts, in the same manner as previously described.

It will be understood that when the second pair of contact members are employed, the blade 22 and cam member 5% are elongated proportionately and a second pair of electrically conductive, flexible straps are employed to interconnect the contact members and the base plate 64 of the contact unit.

The basic components of the switch described hereinbefore, namely the arm-supporting unit 16, the supported arm 18 and the contact unit 20, may be employed to provide a single side break switch, as illustrated in FIGS. 7-9. For this purpose the arm-supporting unit 16 is mounted in manner similar to FIG. 1 upon the upper end of an insulator 10 which is supported conventionally upon a bearing 1th) for axial rotation by means of the lever arm 1G2 and operating link 1%. The locking bolt 50 is inserted into the aligned openings 48 in the arms 32 and 3d of the base and support members, to prevent rotation of the latter member about the pivot bolts 36. The switch blade 22 is rotated from the position of FIG. 1, and secured by the set screw 62, so that its fiat, contacting surfaces are disposed substantially normal to the rotational axis of the insulator 10.

The contact unit 20 also is repositioned 5 0 from the position illustrated in FIG. 1 and mounted upon the upstanding section 106 of an L-shaped bracket, the lower horizontal section 108 of which is secured to the upper end of the fixed insulator, by means of the screws 110. The outer, flared ends of the

contact members

72, 74 thus face laterally outward and are disposed for receiving the blade 22 between them.

Since the blade must be movable between retracted and operative positions relative to the contact members by means of the operating link 1%, the locking members 9t) (FIGS. 5 and 6) and hook cam 94 are removed.

Also, since the arm-supporting contact unit 16 is mounted for axial rotation with the insulator 10, the terminal connector 23 of FIG. 1 preferably is replaced with a terminal connector constructed in the manner illustrated in FIG. 7. The shank end 112 of this connector is secured to the base member 24, as previously described. However, the head end 114 of the connector is bifurcated and the vertically spaced arms thereof are provided with aligned openings for reception of the con necting bolt 116. The bolt serves to connect pivotally the apertured end of a terminal lug 118 to which an electric circuit conductor cable may be secured. During rotation of the insulator to make and break the circuit, the lug pivots to limit flexing of the cable.

In the event it is desired to construct a center side break switch, the switch arm 18 of FIG. 7 is elongated toward the right, as indicated by dash lines, and its extended end provided with a switch blade 22. Associated with this second switch blade is a second switch contact unit 26 mounted upon a second fixed insulator in the same manner as is illustrated in the left hand portion of PEG. 7, but with the diverging outer ends of the

contact members

72, 74 facing in the opposite direction.

The basic components of the switch first described also may be utilized for the construction of a rocker shaft type of air break switch. Referring to FIG. 10 of the drawings,

the arm-supporting contact unit 16 is mounted upon the upper end of an insulator 10, without the terminal connector 28 of FIG. 1, and the insulator is mounted upon a bracket 120 supported pivotally on a base 122 by such means as the pivot pin 124. The mounting bracket includes a depending arm 126 to which is secured, by such means as the clamp 128, a hollow rectangular operating rod 130. Thus, as is well known, rotation of the rod by means of an appropriate tool effects pivotal movement of the insulator and supported unit 16 about pivot pin 124.

The switch arm 18 and

support members

34, 52 are secured against rotation relative to the base member, by means of the locking bolt 50, and the hook cam 94 and locking members 90 are removed, as in the embodiment illustrated in FIGS. 79.

The contact unit 20 is mounted upon a fixed insulator 12, as in FIG. 1, with the exception that the insulator is mounted upon a bevel washer 132 so as to be inclined slightly from the vertical. In this manner the switch blade 22 and arm 18 are disposed substantially normal to the longitudinal axis of the

contact members

72, 74 when the switch is closed.

To the side of the arm-supporting contact unit 16 opposite the contact unit 20, is positioned a third insulator 134 mounted in fixed position upon the common support 14. Terminal connector 136 integral with a base member 138 is secured to the upper end of the insulator. The base member includes an upstanding flange 140 to which is pivotally secured, by means of the pivot pin 142, the lower end of a cable ladder link member 144 of well known construction. The second link member 146 of the ladder is secured at one end pivotally to the upper end of the first link member, by means of the pivot pin 148, and the opposite end of the second link member is secured pivotally to the base member 132 of the arm-supporting unit, by means of the pivot pin 150.

The ladder serves in conventional manner to support an electrical conductor 152 the opposite ends of which are connected to the flange 140 of the base member and to the support member 52 of the arm-suporting unit.

From the foregoing it will be apparent that various types of high voltage air break switches may be constructed from a minimum number of basic components, namely the base and support members of the switch-supporting contact unit 16, the switch arm 18 and blade 22, and the contact unit 20. In the construction of a hookoperated switch, the locking bolt 50 is removed to permit pivotal movement of the switch arm, and the locking members 90 and hook cam 94 are employed. In the construction of a side break switch (FIGS. 79) the locking bolt 50 is installed to secure the switch arm against rotation, the locking members 90 and hook cam 94 are removed, and the contact unit 20 is mounted in horizontal position by means of the simple L-shaped

bracket

106, 108. The terminal connector 28 of FIG. 1 may be replaced, if desired, by the terminal connector illustrated in FIG. 7. In the construction of a rocker shaft type switch, the locking bolt 50 is installed to secure the switch arm against rotation, and the terminal connector 28, locking members 90 and hook cam 94 are removed.

The components of the switch are usable with standard insulators and insulator mountings. The minimum number of components minimize the cost of production and inventory requirements for the construction of a variety of switch types. The minimum number of components also greatly facilitates the assembly and disassembly of the various types of switches, and minimizes the incidence of maintenance and repair.

It will be apparent to those skilled in the art that various changes may be made in the number, size and arrangement of parts described hereinbefore without departing from the spirit of this invention and the scope of the appended claims.

Having now described my invention and the manner in which it may be used, what I claim as new and desire to secure by Letters Patent is:

1. A high voltage air break switch, comprising:

(a) a switch arm-supporting unit including a base member and a support member,

(b) pivot means interconnecting the base and support members,

(e) a switch arm secured to the support member,

(d) a switch blade on the switch arm adjustable rotatably substantially on the axis of the switch arm to selective positions parallel to and perpendicular to the axis of the pivot means,

(e) a contact unit including a base member and a pair of spaced contact members mounted thereon for lateral movement for receiving the switch blade retractably beween them,

(f) means resiliently engaging the contact members and urging them toward each other, and

(g) switch arm locking means securing the base member and support member of the switch arm-supporting unit together releasably against pivotal movement of the support member about the pivot means.

2. The switch of claim 1 including ball and socket connecting means on the base member and contact members of the contact unit mounting the contact members for lateral movement relative to the base member, and a connector bolt extending loosely through aligned openings in the base and contact members coaxial with the ball and socket connecting means.

3. The switch of claim 1 wherein the resilient means comprises a bolt extending through the contact members and having a headed end and an adjustment nut on the opposite end, a pairof springs on the bolt one interposed between the bolt head and the adjacent contact member and the other interposed between the nut and the adjacent contact member, and flexible conductors interposed at one end beween the springs and contact members and secured at their opposite ends to the base member of the contact unit.

4. For use as a side break switch, the switch of claim 1 including an L-shaped bracket, means on one section of the bracket for securing thereto the base member of the contact unit, means on the other section of the bracket for securing the same to an electrical insulator, and means securing the switch blade disposed in a plane substantially parallel to the axis of the pivot means, the base member of the switch arm-supporting unit being adapted for mounting on a rotatable insulator.

5. The switch of claim 1 including blade locking members mounted removably on the outer ends of the contact members and normally restricting the entrance space between the latter for securing the blade between said contact members inward of the locking members, and cam means mounted pivotally on the blade and engageable with the blade locking members to move the latter apart to release the blade, the cam means being at least as wide as the blade.

6. The switch of claim 1 including terminal connector means mounted removably on the base member of the switch arm-supporting unit.

References Cited UNITED STATES PATENTS 1,558,628 10/1925 Purcell 20042 2,224,614 12/1940 Sohles 200-l62 2,303,914 12/1942 Crabbs 200-162 2,546,366 3/1951 Lindae 200162 2,630,510 3/1953 Hoffman et al. 200-162X 2,650,284 8/1953 Volgovskoy 200-162 2,734,955 2/1956 Owens 20048 3,248,509 4/1966 McCloud 200-162 ROBERT K. SCHAEFER, Primary Examiner.

H. I-IOHAUSER, Assistant Examiner.