US1745080A - Disconnecting switch - Google Patents

Description

J 1930. H. J. cRAB Bs 1,745,030

DISCONNECTING SWITCH Filed Nov. 5, 1925 3 Sheets-Sheet l Ill-I XR EF II JTH I 1 1 1 I i WITNESSES: INVENTOR ATTOIRNEY Jam. 28, 1930.

H. J. GRABB$ DISCONNECTING SWITCH I5 Sheets-Sheet 2 Filed Nov. 5, 1925 INVENTOR I Herbert JCr-afiba.

WITNESSES:

a ay/14M.

TTOR'NEY M i-W H. J. CRABBS DI SCONNECTING SWITCH Jan, 2.8, 1930.

3 Sheets-Sheet 3 Filed NOV. 5, 1925 WITNESSES:

Patented Jan. 28, 1930 UNITED STATES PATENT OFFICE HERBERT J. CRAIBBS, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELEGTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVANIA DISOONNECTING SWITCH Application filed November My invention relates to electrical apparatus and particularly to disconnecting switches.

One object of my invention is to provide a disconnecting switch that shall be adaptable both for horizontal and vertical mounting.

Another object of my invention is to provide a disconnecting switch that shall be free from moving joints that are at the same time current-conducting joints.

A further object of my invention is to provide a disconnecting switch in which the moving contact member shall be connected to a terminal member by a flexible conductor having resilient guiding means for controlling the position of the flexible conductor during movement of the movable contact member.

Yet another object of my invention is to provide an-improved housing for the end of the switch blade.

In mounting disconnecting switches, it is customary to support the current-carrying elements of the switch on petticoat insulators. Such insulators, when supported in an inverted position, are capable of collecting moisture on the undersides thereof, and such bodies of moisture cause dangers of flash-over between the current-conducting members and ground and between currentconducting members themselves. Such moisture also soaks into and along the insulator pins with the result that the insulators are frequently broken by the expansive and contractive forces incidental to freezing and thawing. Accordingly, it has been found necessary to so design disconnecting switches that any petticoat insulator on the movable contact member shall always be in such a position that as to be self-draining.

Heretofore, it has been customary to limit the application of any particular disconnecting switch to either a horizontal or a vertical mounting. With my improved disconnectin switch, I am able to change the moutning o the switch from the vertical to the horizontal position without inverting any of the petti coat insulators by simply changing the supporting arm that carries the petticoat insulator supporting the movable contact member. Disconnectin switches are frequently mounted out-o -doors and must be operated 5, 1925. Serial No. 67,021.

under allsorts of weather conditions such as when the entire apparatus is covered with ice or sleet. It has, therefore, been found advantageous to house the end of the switch blade in such manner that the housing does not carry the major portion of the current.

In providing for opening and closing such housing, I take advantage of the fact that ice is weakest in tension and have so designed the housing that there is no opportunity for ice to be under compression or direct shearing stresses during the movements of the housing parts. I am enabled to secure this result by providing a longitudinally split housing that is flexibly mounted and the constituent parts of which are each provided with a cam surface that cooperates with the switch blades in a wedging action during opening and closing movements thereof.

In the accompanying drawings,

Figure 1 is a view in elevation of a disconnecting switch embodying myv invention, mounted in the vertical position,

Fig. 2 is a similar view showing the switch mounted in a horizontal position,

Fig. 3 is an elcvational view of the housing for the contact members of the switch,

Fig. 4 is a view, partially in section and partially in elevation, of the housing taken along the section line IV-IV of Fig. 3, and

Fig. 5 is a perspective view of one of the housing members.

My invention comprises, in general, a frame 1 that supports a pair of spaced insulators 2 and 3, which, in turn, support a stationary contact member 4 and a terminal member 5, respectively, between which is mounted a shaft 6 that-supports and actuates an insulator 7 that serves as a mounting for a mov able contact member 8. The stationary contact member 4 terminates in a weather-proof housing 9,0f particular construction.

The'frame 1 may consist of any arrangement of angle or channel irons or a slate base, as desired. In the preferred construction, however, the disconnecting switch is on the under surfaces thereof. Accordingly, it is essential that the insulators 2, 3 and 7 shall always be so mounted as to be selfdrainin in order to avoid danger of flashovers from the electrical-current-carrying points to ground and between each other an deterioration incidental to freezing and thawin Themsulator 2 supports the stationary contact. member 4 that terminates in the housing 9 and an arcing horn 11. The arcing horn 11 is preferably resiliently mounted, as at 12, in order to afford greater flexibility and thereby to permit the contact members 4 and 8 being further removed from each other at the periods of engagement and disengagement of the arcing horns.

The insulator 3 supports the terminal 5 that may be of any preferred type, of which there are a large number on the market, and, in addition thereto, it supports a relativel long and stiff spring 13 that is provided wit openings 14.

The material of the spring 13 is such that it may have movement of a relatively large range and, at the same time, support the weight of a flexible conductor 15 threaded through the openings 14 for connectingthe moving contact member 8 to the terminal member 5. The spring 13 prevents the loops of conductor 15 from falling across ad'acent phases of the switch or switches uring movement of the movable contact member 8 and, at the same time, eliminates the necessity for the elaborate knuckle joints and struts, heretofore employed in such "disconnecting switches. j 9

'The shaft 6 is operated byflany' suitable mechanism not shown). A; collar 16 is clamped to t e shaft 6, one part of which carries lugs 17 that cooperate with suitable springs 18 in the frame 1 for preventing injurious jars during the movement of the switch.

In Fig. 1, the upper part of the collar 16 is shown as comprising an elongated arm 19 that terminates in a seat 21 for the insulator 7. The insulator 7 carries a relativel movable contact member 8 that is in the orm of a switch blade for engagement with the stationary contact member 4. The switch shown in Fig. 1, is particularly adapted for vertical mounting as the length and inclination of the arm 19 is such that the insulator 7 is self-draining when the switch is in a closed or solid-line position and when it is in the open or dotted-line position.

In the form of my invention shown in Fig. 2, the upper part 22 of the collar member 16 directl serves as the seat 23 for the insulator 7. T is form of my invention is particularly adapted for the horizontal mounting of theswltch, since the insulator 7 is in a self-draining position both in its closed or full-line position or in its open or dotted- .notches 3 line position. The insulator 7 carries also an arcing horn 24 for cooperation with the arcing horn 11. A spring 25 may be inserted at the base of the arcing horn 24 if desired.

Referring particularly to Figures 3 to 5, the housing 9 for the contact members comprises two complementary castings or sheetmetal stampings 30 that may be termed of trough or clam shape. The members 30 engage each other along substantially their entire peripheries, thereby enclosing contact fingers 31 that engage the movable contact member 8 and complete the principal electrical circuit. The purpose of the housin section 30 is primarily that of protection and not that of current carrying. The housing sections 30 are each supported by a flexible strip of metal 32, such as bronze that is connected by suitable bolts 33 to a base portion 34 of the switch member 4. The contact fingers 31 are independently supported by the ase portion 34 y means of bolts 35. The base 34 fits in between the metal strips 32 and substantially closes the back part of the housing 9.

The met-a1 strips 32 further serve to bias the housing elements 30 into firm engagement -with each other. The housing members 30 are provided, at their outer ends,.with outturned cam edges 36 that cooperate with the movable contact blade 8 for the purpose of prying or wedging the parts 30 apart during the opening and closing movement of the housing.

The lower edges of the housing 30 are provided with notches 37 for the reception of the switch blade 8 when the switch is in a closed position. The housing '9, therefore completely encloses and protects the end 0 the switch of the movable contact blade 8.

- Since ice and sleet are weakest when under tension, I am enabled to open the housin 9 with a minimum effort for the reason t at the only force that such ice can exert is in tension across the line of cleavage defined b the edges of the sections 30. Accordingly,

have provided cam surfaces 38 on the upper blow, which blow is centered at the edges of the sections 30 that are then split apart. After the blade 8 has entered the notches 37, the housin 9 closes under the influence of the spring lades 32. When it is desired to 0 en the switch, the blade is moved outwar ly against the inner surfaces 38 of the and the housing elements 30 are split apart.

again isposition of the insulators 2, 3 and The compression and bending forces during 7 is such that they are subjected to 'combingd' ,t e circuit-closin movement and combine tension and ben ing forces during the circuitopenin movement, I In t e o eration from the open to the closing position, the operator causes shaft 6 'to rotate in a clockwise direction, where upon, the arcing horn 24 is brought into ongagement with the arcing horn 11, the flexible conductor is extended and the spring 13 is slightly flexed during the turning of the movable contact member 8 into enga ement with the housing 9. When the move le contact blade 8 engages thestationarv contact member 4, the housing sections are) split apart andthe blade 8 enters the notches 3 and between the contact fin rs 31, whereupon the circuit is complete If it is desired to open the switch, the shaft 6 is rotated in a counter-clockwise direction, when the foregoing steps take place in reverse order.

It will thus be seen that I have devised a disconnecting switch that may be easily fitted for either horizontal or vertical mountmg. I have also eliminated the knuckle jomts, braces or the 1ike,by utilizing aflexible connector between the terminal and the movable contact member which is guided by a springof novel construction.

I have further devised a housin for the end of the switch blade, of such orm that the switch blade is completely housed andin which any resistance offered by ice or the like to movement of the housing, must be along the lines of tension in the ice. Since ice is weakest in tension and since the blade members of such disconnecting switches move with considerable force I am able to break such an ice coating without undue expenditure'of energy.

- While I have'shown but a single embodiment of my invention, further 0 anges and modifications ma be made'therein without departing from t e spirit and scope thereof, and I desire therefore, that only such limitaplaced thereupon as are imfined b the engagin edges whereby any ice y to Eeep the shield closed isor sleet tending broken undertensmn.

2. A housing. for a switch structure split longitudinally and having internal and external cam surfaces on the subdivisions there- .of for cooperation with a switch blade for openin the housing by the lateral displacement'o a portion thereof.

3. vThe combination with a Switchblade, of a longitudinally-split ice shield for the end thereof, the ice shield having an internal and an external cam surface; for co-operation with the switch blade for opening the ice shield by the lateral displacement of a portion thereof. I 1 4,1 1 combination with a disconnectin switch including a base supporting a termin anda stationary contact in spaced relation, a shaft disposed intermediate said terminal and said contact, and an insulator for supporting a movable contact in electrical connection with said terminal, detachable clamp-.

the switch is mounted with its base horizontal,

and a second clampin means interchan eable with the first sai clampin means or supporting said insulator on sai shaft in a l difierent relation to said base when the switch is mounted with its base in vertical position. 5. In combination with a disconnecting switch, elements includinga base, a movable contact, a rocking shaft for actuating the contact, and a Petticoat insulator for mountin the said contact in fixed relation with sai shaft, a pair of interchangeable supporting members, each ofwhich is adapted to cooperate with the shaft. to support the said insulator, whereby the tion of the proper member for its support correspon to the horizontal or vertical switch comprising a stationary contact member, a movable contact member, an insulator for sup orting said movable contact member, an a shaft adapted for rotatably sup-- porting said movable contact member, interchangeable clamps for mounting said movable contact member on said shaft in either of two predetermined relations.

'1' In combination with a disconnecting switch comprising a stationary contact member, a movable contact member, an insulator for supporting said movable contact memher, an a shaft adapted for rotatably portmg said ator shaft in either of two lations.

I n testimony whereof, I have hereunto subpredetermined remanners. omens.

an I interchangeabl; clampsfor mountingsaid insulator on said 'rny'name this2 3rd day-of October,

coat insulator may be retained in a position in which said I etticoats are self-draining through the selec

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