US2163398A - Electric switching device and mounting means therefor - Google Patents

Description

June 20, 1939. H R N 2,163,398

ELECTRIC SWITCHING DEVICE AND MOUNTING MEANS THEREFOR Filed Nov. 50, 1937 Inventor: B enjamin R. Hermann,

y w m His ULor'ney Patented June 20, 1939 UNITED STATES PATENT OFFICE ELECTRIC SWITCHING DEVICE AND- MOUNTING MEANS THEREFOR Benjamin It. Hermann, Lanesboro, Mass, assignor to General Electric Company, a corporation of New York Application November 30, 1937, Serial No. 177,244 14 Claims. (01. 200 114) The present invention relates to electric switchmanually moving the door and fuse holder into ing devices and mounting means. therefor and and out of operative position. The door and has for an object the provision of a simple and fuse holder are supported in the casing by means low cost switching device of the enclosed type of a hinge lever 24 one end of which is pivotally having improved construction and arrangement attached to door boss 21, as indicated at 25, and 5 of parts and improved mounting means for inthe other end of which has a hook-shaped porstallation of the device directly upon a bushing tion 26 arranged to engage a hinge pin 21 carsupported terminal of a transformer or like ried by hinge bracket 28. The hinge lever norpiece of electric apparatus. mally is held in rigid relation to fuse holder l4 Other objects and the details of that which I by means of a portion 35 of a fuse link extend- 10 believe to be novel and my invention will become ing out of the lower end of the fuse holder and apparent from the following description and the secured to the lever by any suitable form of claims appended thereto taken in conjunction clamping means indicated at 35. With this with the accompanying drawing in which Fig. 1 arrangement, upon rupture of the fuse link in 5 illustrates a rear view of an exemplary switchfuse holder M, the door and fuse holder drop ing device, in the form of an enclosed fuse cutdownwardly and outwardly to a position wherein out, and mounting means therefor embodying the fuse holder is isolated from upper contact ll, my invention; Fig. 2 is a longitudinal oross-secthis operation being in a manner similar to that tion through the housing of the cutout showing described in detail in connection with the dropthe construction and arrangement of the parts out fuse cutout of my patent No. 2,081,813, issued 20 thereof; Fig. 3 is a detail view of an improved May 25, 1937, and assigned to the assignee of mounting bracket employed in supporting the the present invention.

cutout; and Fig. 4 illustrates diagrammatically Hinge bracket 28 serves as the lower terminal the manner of mounting the cutout and bracket contact of the cutout and forms part of an elecon a transformer terminal bushing. trically conductive bolt 32 which extends out- 25 Referring to the drawing, Hi designates a caswardly through an opening in the rear wall of ing of porcelain or other suitable insulating rnacasing l0 and which is fixedly anchored in the terial in which is mounted an upper terminal opening by means of suitable cement, indicated contact ll having spring fingers :2 adapted to at 33. The outer end of this bolt is threaded for receive therebetween the upper terminal of a reception of a clamping nut 34 and a lock washer 30 switching element, such as the terminal cap is 35 and is arranged to extend through an openof an insulating fuse holder l4. Contact II has ing 36 in the web portion 3? of a mounting also a. contact finger l5, backed by a spring strip bracket 38, which web portion 31 is adapted to IE arranged to bear downwardly on a fuse holder bear against the rear face of easing l0, as indi- 35 terminal cap. Although a fuse holder is emcated in Figs. 1 and 2. 35 ployed in the exemplary embodiment illustrated, Mounting bracket 38, the details of which are it will be evident from the ensuing description shown in the perspective view of Fig. 3, is comthat the present invention is not limited to this prised of any suitable metal having springiness particular form of switching element. For exand resistance to vibration fatigue failure. This {0 ample, an electrically conductive switcl nng blade bracket is formed with a substantially flat and may be substituted for the fuse holder if it is de relatively thin portion 39 having an upper reinsired, as is sometimes the case, to employ the forcing ridge 40 and a lower reinforcing ridge 4i. switching device only for connecting and dis In the outer end of portion 39 is a socket openconnecting purposes without fuse protection. ing 42 disposed substantially in the plane of por- 45 Just beneath contact II is an electric creepage tion 39 and adapted to receive a terminal stud 45 and gas barrier ll formed integrally with the 43 of a transformer or like piece of electric appacasing and arranged to retard the rising of arc ratus and to rest upon the upper end of the gases from the lower end of an expulsion fuse terminal supporting bushing 44, as shown in Figs. holder, such as the one illustrated, into the space 1 and 2.

around the contact H in the upper part of the Casing I0 is clamped, by means of bolt 32, nut 50 housing. The illustrated fuse holder I4 is sup 34 and washer 35, so that the rear face of the ported by bosses 2t and 2| formed integrally with casing bears tightly against the lower face of web a door 22, constructed of suitable insulation, 31. This web is arranged so that it lies in a which is adapted to close the open front of casplane at an acute angle to the plane of the flat ing l0 and which has an eyelet handle 23 for portion 39 of the mounting bracket or, in other 55 words, so that it lies in a plane at an angle of less than 90 degrees to a plane extending through terminal stud 43 normal to the plane of opening 42. As a result of this expedient, casing IQ is supported, as best shown in Fig. 2, so that it is tilted forward at an acute angle to a plane passing through the axis of terminal stud 43 so that are gases discharged from the lower end of fuse holder 14 will not be directed straight downwardly on to the lower end of bushing as and the adjacent portion of the cover of the transformer Q5 (see Fig. 4) to damage the bushing or cause short circuiting arc-over between conducting parts. The forward tilting or" the casing also prevents leakage of rain water into casing I when door 22 is normally closed and prevents the entrance of rain-sleet, and snow into the casing when the door is in its open dropped-out position previously referred to. Bracket 38 has spaced apart flanges es projecting from the lower face of web portion 37 of the bracket and arranged to receive the cutout casing therebetween to prevent rotation of the casing relative to the bracket about bolt 32.

As a further result of the formation of the bracket as previously described, the flat portion 39 lies in a plane substantially transverse to the axis of fuse holder M. Due to its relative thinness, portion 39 of the bracket flexes resiliently upon recoil of the fuse holder due to fuse operation or upon slamming of the door, thus providing a cushioning effect to prevent damaging shock to the supporting bushing M which commonly is of insulating ceramic material relatively easily damaged by shock. Reinforcing ridges 49 and 4| are arranged to give sufficient stiffness to the bracket for proper support of the cutout while at the same time permitting the desired flexibility of portion 39 of the bracket.

Also, in accordance with the teachings of my copending application, Serial No. 176,271 filed November 24, 1937, and assigned to the assignee of the present invention, it is preferable that bracket 38 be provided with a plurality of slots 41 communicating with socket opening 42 and extending radially of the opening with the slots arranged in pairs and the slots of each pair disposed diametrically opposite each other, as best shown in Fig. 3. These slots are arranged to receive a keeper element' lll extending through a transverse slot 49 in terminal stud B3 to prevent rotation of bracket 38 about the terminal stud. By reason of the plurality of pairs of slots 41, it is possible selectively to position the bracket and the cutout casing attached thereto so that the door 22 is readily accessible from a transformer supporting pole 5B or similar mounting structure and so that the lower discharge end of fuse holder I4 is directed outwardly over the side of the transformer, as indicated in Fig. 4. An added advantage of the forward tilting of the casing when the cutout is mounted as shown in Fig. 4, is that a service man is protected from injury by gases discharged from the lower end of the cutout in case of fuse operation during servicing. With the arrangement described, the cutout casing may be mounted in any desired manner iin different transformer installations wherein the supporting pole and terminal bushing have different physical relationships with respect to each other and the transformer casing.

In an installation of the type diagrammatically illustrated in Fig. 4, the lower contact of the cutout is connected to the transformer terminal per contact has secured thereto, as by means of a screw 5|, one end of a line lead indicated at 52. Also, contact I I may have secured thereto one end of a lead 53 extending from a lightning arrester indicated at 54 as being mounted on the side of the transformer -45. Thus, there is provided a unitary transformer assembly embodying both overcurrent and overvoltage protection.

From the foregoing description, it will be seen that the switching device of my present invention provides a means for securing in outdoor installations, such as on rural type transformers and the like, an improved fusing protection with the advantages of the enclosed type fuse cutout, including superior insulation, safety to service men, and weather protection, which advantages it is not possible to secure with the line suspension fuse cutouts and bushing mounted open type fuse cutouts of the type heretofore commonly employed. My invention provides also an improved switching device of the enclosed type, which, while having the advantages above set forth, still is of such simple and low cost construction that it may be embodied to advantage with other protective equipment, such as a lightning arrester, in a transformer assembly of the unit type so as greatly to facilitate the installation of the transformer assembly on a pole or other suitable supporting structure in the field.

What I claim as new and desire to obtain by Letters Patent of the United States is:

1. The combination with an electric switching device of the enclosed type having an insulating housing with a pair of spaced terminal contacts therein and means for supporting in the housing an electric switching element connected between said contacts, of a springy mounting bracket of electrically conductive material secured to said housing and having means for attachment to a bushing supported terminal stud of a transformer or the like, and means providing electric connection between one of said contacts and said mounting bracket.

2. The combination with an insulating housing for an electric switching device, of a contact mounted in the housing, an electrically conductive mounting bracket attached to the housing and provided with means for attachment to an electrically conducting support for the housing, and an electrically conductive element mechanically and electrically connected with said bracket and extending into the housing, which said element is provided interiorly of the housing with means for pivotally supporting an electric switching element for engagement with said contact.

3. The combination with an electric switching device of the enclosed type including an insulating housing comprised of a casing having an open front and a door movably mounted for closing said open front, of a mounting bracket havinga substantially flat and relatively thin springy por tion provided adjacent one end with a socket opening lying substantially in the plane of said flat portion and adapted to receive a supporting stud, said bracket having adjacent theother end of said first mentioned portion a web portion disposed at an acute angle to the plane of said first mentioned fiat portion, and means securing said casing to said bracket with the rear face of the casing bearing against the underneath face of said web portion, whereby said open front of the casing is maintained in a plane tilted forward at an acute angle to the plane of said first mentioned fiat portion and said socket opening,

4, The combination with an electric switching device of the enclosed type having a housing of insulation with spaced contacts mounted therein and means for supporting an electric switching element connected between said contacts, or" a mounting bracket for said housing having an attachment portion arranged to bear against the rear face of said housing and a pair of arms pro jecting from said attachment portion in spaced relation to each other for receiving said housing therebetween, and means for securing said housing in the seat provided by said attachment portion and projecting arms.

5. In an electric switching device, an enclosing housing of insulation, a pair of spaced contacts mounted in the housing, hinge means for pivotally supporting an electric switching element in the housing connected between said contacts, and an electrically conductive mounting bracket for said housing having means for attachment to a terminal stud of a transformer or the like, one of said contacts having an electrically conductive element extending exteriorly of said housing and connected to said bracket for securing the housing to the bracket.

6. In an electric switching device of the enclosed type, a housing of insulation, spaced contacts mounted in the housing and hinge means for pivotally supporting a switching element in the housing removably connected between the contacts, one of the contacts having an electrically conductive mounting element extending exteriorly of the housing for attachment to a support for the housing.

'7. In an electric switching device of the enclosed type, a housing of insulation and a pair of contacts mounted in the housing, one of which contacts is provided interiorly of the housing with means for pivotally supporting a switching element removably connected between the contacts and said one contact having an electrically conductive mounting element extending exteriorly of the housing for attachment to a support for the housing.

8. In an electric switching device of the enclosed type a housing of insulation, spaced contact means mounted in the housing and a mounting member extending through a wall of the housing in fixed relation thereto, which said member is provided exteriorly of the housing with means for attachment thereof to a support for the housing and is provided interiorly of the housing with means for pivotally supporting a switching element removably connected between said contact means.

9. In an electric switching device of the enclosed type, a housing of insulation, an upper contact mounted in the housing, and a lower contact mounted in the housing, which said lower contact is provided interiorly of the housing with a hinge bracket for the pivotal support of an electric switching element and has an electrically conductive portion extending exteriorly of the housing for attachment to a support for the housing.

10. In an electric switching device of the enclosed type, a housing including an insulating casing having an open front, a contact mounted in the housing, and an electrically conductive bolt fixedly mounted in the rear wall of the housing in spaced relation to said contact, which bolt has a threaded portion extending exteriorly of the housing for attachment thereof to a support for the housing and a portion extending interiorly of the housing provided with means for supporting an electric switching element for removable engagement with said contact.

11. An electric switching device including in combination an enclosing housing of insulating material, an electrically conductive mounting bracket for said housing having means for attachment to an electrically conductive supporting stud and having also a web portion arranged to bear against one of the walls of said housing, a pair of contacts mounted in said housing, one of said contacts having means for supporting an electric switching element in the housing connected between the contacts and having also a portion extending exteriorly of the housing and connected with said web portion for securing the housing to said bracket, and means carried by said bracket for preventing displacement of the housing relative to the bracket.

12. In a housing for an electric disconnect switch, fuse cutout and the like, a box-like casing of insulation having top, rear and side Walls and an open front, which open front provides for manipulation of an electric connection element to and from a connected position between spaced contacts mounted in the casing and which open front is adapted to be closed by a removable door, and upper and lower contacts mounted in the casing in substantially fixed spaced relationship for removable engagement by an electric connection element, one of which contacts has an electrically conductive mounting element provided with means for mounting attachment to an electrically conducting support for the cas- 13. In an electric switching device, a box-like insulating casing having top, rear and side walls and an open front providing for manipulation of an electric connection element to and from connected position between spaced contacts mounted in the casing, a door for closing said open front, upper and lower contacts mounted in the casing in substantially fixed spaced relationship, one of Which contacts has an electrically conductive mounting element provided with means for mounting attachment to an electrically conducting support for the casing, and means for supporting an electric connection element in the casing in connected position between said contacts, which said supporting means is arranged to provide for movement of an electric connection element relative to said contacts to a disconnected position.

14. In an electric switching device, a box-like insulating casing having top, rear and side walls and an open front, a door for closing said open front, an upper contact mounted in said casing, a lower contact mounted in the casing and having an electrically conductive mounting element provided with means for mounting attachment to an electrically conducting support for the easing, and means including said lower contact arranged to support an electric connection element in the casing in connected position between said contacts and to provide for movement of the electric connection element relative to said contacts to a disconnected position.

BENJANIIN R. HERMANN.

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