US3115053A

US3115053A - Tool for modifying electrical panelboards

Info

Publication number: US3115053A
Application number: US84677A
Authority: US
Inventors: Chester A Bernier
Original assignee: Square D Co
Current assignee: Schneider Electric USA Inc
Priority date: 1961-01-24
Filing date: 1961-01-24
Publication date: 1963-12-24
Anticipated expiration: 1980-12-24

Description

1963 c. A. BERNIER 3,115,053

TOOL FOR MODIFYING ELECTRICAL PANELBOARDS Filed Jan. 24, 1961 INV EN TOR. fiervzzer United States Patent Ofiice 3,115,653 Patented Dec. 24, 1963 3,115,053 TOOL FOR MUDIFYING ELECTRICAL PANELEOARDS Chester A. Bernier, Lexington, Ky., assignor to Square D Company, Park Ridge, III., a corporation of Michigan Filed Jan. 24, 1961, Scr. No. 84,677 1 Claim. (CI. 81-15) This invention relates generally to a tool for modifying electrical panelboards, and more particularly to a tool intended to be used by qualified electricians to bend up sheared portions of a registry or rejection bracket on a mounting mail for circuit controlling devices to permit the panelboard to accommodate circuit controlling devices of a relatively high current rating at selected locations which, because of the presence of an interference means, could not be accommodated at those locations prior to the bending operation.

The object of the invention is to provide such a tool, it being understood that the required modification of a mounted panelboard by an unauthorized person cannot readily be made with conventional tools.

FIGURE 1 is a fragmentary sectional view of an electrical panelboard of the type for which the tool of the present invention is designed;

FIGURE 2 is an enlarged sectional view of the mounting rail of the panelboard of FIGURE 1 and the rejection bracket attached thereto, illustrating a portion of the tool of the present invention as it is received by the mounting rail and rejection bracket prior to bending up a sheared tongue portion of the rejection bracket;

FIGURE 3 is a view similar to 'FIGURE 2, but showing the tool in position on the rejection bracket after it has completed the bending up of the sheared tongue;

FIGURE 4 is a perspective view of the parts in the relative positions shown in FIGURE 3;

FIGURE 5 is a view showing the tool in full;

FIGURE 6 is an enlarged sectional view of the mounting rail and rejection bracket prior to the bending up or" a sheared tongue portion, showing a portion of a circuit controlling device having interference means; and

FIGURE 7 is a view similar to FIGURE 6, but showing the sheared tongue portion bent up so that the rcjec tion bracket can accommodate the interference means of the circuit controlling device.

An electrical panelboard 12 of FIGURE 1 includes a metal enclosure 14 having side walls 15, only one of which is shown, and a bottom wall 16. A trim member 18 has a frontal opening 19' to provide access into the interior of the enclosure 14. The opening 19 is provided with a door 2! and the trim member 18 is secured to the enclosure 14 as by clamps such as a clamp 21.

An interior assembly 22 is secured by any suitable means to the bottom wall 16 of the enclosure 14 and mechanically supports two parallel rows 23a and 23b of circuit controlling devices such as circuit breakers. As shown in FIGURE 1, a circuit breaker 24 in the row 23a may have a relatively low current rating and a circuit breaker 25 in the row 2311 may have a relatively high :urrent rating.

The interior assembly 22 comprises a pan 26 the side edges of which are folded upwardly to form a pair of ipaced parallel upstanding flanges 28, only one of which is shown. The flanges 28 are provided with rolled-over Jead portions or mounting rails 30 which function as elements of a mounting system for the circuit breakers.

Two longitudinally extending bus bars 32, only one J'f which is shown, are mounted in spaced parallel rela :ionship on an insulating support 36 carried by the pan 26. A plurality of terminal connectors 37, each electrially and mechanically connected to one of the bus bars 32 in alternate arrangement lengthwise of the panelboard 12, extend transversely toward the other bus bar to define longitudinally spaced mounting areas for the circuit breakers and to provide for electrical connection of the circuit breakers to one of the bus bars 32.

The circuit breakers are provided with identical conductive spring jaw clips, such as clips 38 and 359 of the

circuit breakers

24 and 25, respectively, that extend downwardly for making electrical connection to the connectors 37. Each circuit breaker in the rows 23a and 23b is electrically connected to one of the connectors 37 and thus to one of the bus bars 32.

As best shown in FIGURES 6 and 7, the circuit breaker 25 of relatively high current rating is provided near its outer end with a suitable recess 43 for receiving a spring mounting clip 44) having spaced

spring jaws

41 and 42 which clampingly receive the bead 30 on one of the flanges 28 of the pan 26.- The jaw 42 extends farther downwardly than the jaw 41 to provide an interference means. The outer end of the circuit breaker 24 of relatively low current rating is not shown, but may be provided with a spring mounting clip similar to the clip 40 but with both of the jaws of the same length as the jaw 41, so that no interference means is provided on the circuit breaker 24.

Each of the flanges 28 has an elongated registry or rejection bracket 44, best shown in FIGURE 4, suitably secured thereto. The brackets 44 are generally L-shaped with a leg portion 45 secured to one of the flanges 28 and a leg portion 46 extending outwardly therefrom and having a rolled-over edge portion 47 and a plurality of longitudinally spaced sheared tongue portions 45. The leg portions 45 may be dimpled as at 49 to provide projections under the tongue portions 48 for the purpose of afiording extra protection in preventing bending of the tongue portions 48 downwardly.

FIGURE 6 illustrates how the extended jaw 42 of the clip 40 on the circuit breaker 25 forms an interference means preventing the mounting of the clip 4t} on the mounting rail 30 when the sheared tongue portion 48- of the rejection bracket 44 at the selected location for mounting of .the circuit breaker 25 has not first been bent upwardly.

FIGURE 7 illustrates how the jaw 42 of the clip 40 can be accommodated by the rejection bracket 44 after the selected sheared tongue portion 48 has been bent upwardly by the tool of the present invention.

The tool of the present invention is indicated in FIGURES 25 by the numeral 59. It is formed of flat stock, as can be seen in FIGURE 4, and has the general outline shown in FIGURE 5. It might be said generally to comprise a body portion 51, a handle portion 52 extending angularly from one end of the body portion 51 and curving at the juncture to provide a finger hold portion at 53, and a rounded end portion 54 having a U-shaped slot 55 opening to a side of the tool and adapted to receive the rolled-over edge portion 47 of the leg 46 of either of the brackets 44, as shown in FIGURE 2. A recess 56 is provided adjacent the U- shaped slot 55 to provide clearance for the bead or mounting rail 36, as shown in FIGURE 2. The provision of the U-shaped slot 55 in the rounded end portion 54 results in formation of a prong, jaw, or prying portion 57 on the opposite side of the slot 55 from the recess 56. The prong or prying jaw 57 extends beyond the edge of body portion 51 and is dimensioned to fit within the opening in either of the rejection brackets 44 provided by the bending up of a sheared tongue portion 43. The prong or prying jaw 57 may be thought of as the output end of a lever, while handle portion 52 may be considered the input end.

The tool 58 is used to bend a sheared tongue portion 48 upwardly by placing it in the position shown in FIGURE 2, so that the bead or mounting rail 30 is received in the recess 56 and the rolled-over edge portion 47 is received in the slot 55' and the prying jaw 57 is beneath the desired tongue portion 48. Rotation of the tool clockwise in FIGURE 2 to the position shown in FIGURE 3 effects the bending of the tongue portion 48 upwardly. A circuit breaker of relatively high current rating, such as the circuit breaker 25, having an extended jaw 42, can then be received by the rejection bracket 44 at that point, as shown in FIGURE 7.

The geometry of the panelboard 12 is such that it is not possible to bend a sheared tongue portion 48 upwardly using conventional tools, such as a pliers or screw driver. The location of the registry or rejection brackets 4 with respect to one of the side walls 15 and the bottom wall 16 does not permit location of a conventional tool at a proper angle to be effective. Thus a householder cannot readily install a circuit breaker of relatively high current rating, such as the circuit breaker 25, in a circuit safely intended to be used with a circuit breaker of relatively low current rating, such as the circuit breaker 24.

Having thus described the invention, I claim:

For use with an electrical panelboard having a beaded mounting rail for circuit breakers and a rejection bracket extending angularly from said mounting rail and having sheared tongue portions and a rolled-over edge portion, a tool for bending up said sheared tongue portions comprising a flat one-piece member having a body portion, a handle portion extending angularly from one end of said body portion, and a generally semi-circular rounded end portion at the other end of said body portion, said body portion having an opposed pair of generally parallel straight side edges, one of said straight side edges merging tangentially into a curved edge of said rounded end portion, said member having a generally U-shaped slot therein adjacent said curved end portion, a curved inner edge of said slot being adapted to rotatively engage said rolled-over edge portion of said rejection bracket during the upward bending of said sheared tongue portions thereof, said U-shaped slot having a pair of opposed straight side edges one of which merges angularly into a curved edge of said generally semi-circular rounded end portion to define a prying jaw, said U-shaped slot opening to the other straight side edge of said body portion and having its opposed straight side edges inclined toward said handle portion, and said other straight side edge of said body portion having a recess therein, an edge of said recess merging angularly into the other straight side edge of said U-shaped slot and said recess providing clearance for said mounting rail.

Cole June 22, 1920 Brown Oct. 9, 1951