US3693137A - Connector kit attachable to existing neutral bar assembly - Google Patents

Connector kit attachable to existing neutral bar assembly Download PDF

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Publication number
US3693137A
US3693137A US125717A US3693137DA US3693137A US 3693137 A US3693137 A US 3693137A US 125717 A US125717 A US 125717A US 3693137D A US3693137D A US 3693137DA US 3693137 A US3693137 A US 3693137A
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United States
Prior art keywords
kit
installation
connector
mounting platform
support plate
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Expired - Lifetime
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US125717A
Inventor
Walter T Brumfield
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Schneider Electric USA Inc
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Square D Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R9/00Structural associations of a plurality of mutually-insulated electrical connecting elements, e.g. terminal strips or terminal blocks; Terminals or binding posts mounted upon a base or in a case; Bases therefor
    • H01R9/22Bases, e.g. strip, block, panel
    • H01R9/24Terminal blocks
    • H01R9/2483Terminal blocks specially adapted for ground connection

Definitions

  • An object of the invention is to provide a connector kit rigidly securable in the field to a stepped pair of neutral bars of the neutral bar assembly of an existing electrical panelboard and enabling the assembly to accept a larger wire than it was originally designed to accept, the connector kit having a good electrical connection to the assembly after installation and being able to withstand the higher clamping torque required for the larger wire.
  • FIG. 1 is a front view of a prior existing neutral bar assembly
  • FIG. 2 is an end view of the prior neutral bar assembly taken from the right-hand side of FIG. 1;
  • FIG. 3 is a perspective view of a connector body of a connector kit constructed in accordance with the invention.
  • FIG. 4 is a perspective view of a stepped mounting bracket of the connector kit
  • FIG. 5 is a perspective view of a support plate of the connector kit
  • FIG. 6 is a perspective view of a clamping screw of the connector kit
  • FIG. 7 is a top view of a neutral bar assembly similar to the prior existing neutral bar assembly of FIGS. 1 and 2 but having a pair of the connector kits of this invention secured thereto;
  • FIG. 8 is a front view of the neutral bar assembly of FIG. 7;
  • FIG. 9 is a fragmentary sectional view taken along the line 9-9 of FIG. 8.
  • a prior existing neutral bar assembly 11 of FIGS. 1 and 2 and a modified neutral bar assembly 12 of FIGS. 7-9 having the connector kit of the invention secured thereto each include a molded plastic base 13 having a mounting bracket 14 secured thereto by a pair of screws 16 (FIG. 7) threaded into the bracket from the underside of the base and having head portions (not shown) recessed therein.
  • Each of the bars is preferably formed by the method disclosed in US. Pat. No. 3,228,094 issued Jan. I l, 1966, and if desired, the bars 18 and 20 may have spring clip clamping shoes mounted on their clamping screws 26 as shown more fully in US. Pat. No. 3,426,319 issued Feb. 4, 1969.
  • the bars 17 and 19 are provided with clamping screws 27.
  • verted screw 30 which extends through a lower portion of the body 28, is threaded into the tang 14a, and extends with clearance sufficiently .into a hole in a spacer 32 in a wire receiving aperture 28a of the body 28 to prevent the spacer 32 from sliding out of the body 28. Overhanging portions 28b of the body 28 prevent the spacer 32 from rising off the screw 30.
  • a clamping screw 34 is threaded into the body 28 to clamp the main neutral wire (not shown) of an electrical panelboard against the spacer 32.
  • The: clamping screw 34 is provided with a hexagonal recess 34a (FIG. 7) for receiving a hexagonal socket wrench.
  • the connector kit of this invention includes a stepped mounting bracket 36 best shown in FIG. 4, a support plate 38 best shown in FIG. 5, a connector body 40 best shown in FIG. 3, a clamping screw 42 best shown in FIG. 6, and a mounting screw 44 (FIG. 9).
  • two of the connector kits are mounted on the neutral bar assembly 12 as shown in FIGS. 7-9.
  • Each bracket 36 includes a generally square mounting platform portion 36a having a central threaded hole 36b extending therethrough.
  • Each connector body 40 is generally in the shape of a square prism and has a hole 40a extending therethrough from front to back for receiving a wire conductor and a threaded hole 40b (FIG. 9) extending from the top into intersecting rela tionship with the hole 40a for receiving the respective clamping screw 42.
  • Each clamping screw 42 is provided with a hexagonal recess 42a (FIG. 7) for receiving a hexagonal socket wrench.
  • a hole 40c aligned with but of smaller diameter than the hole 40b is provided for receiving the mounting screw 44.
  • the hole 400 is enlarged at its upper end to accommodate an enlarged head portion of the screw 44.
  • the screw 44 is threaded into the hole 36b to secure the body 40 to the platform portion 36a.
  • bracket 36 At the rear of the mounting platform portion 360 the bracket 36 is provided with a riser portion 36c (FIG. 4) leading to a fastening portion 36d parallel with the platform portion 36a and having a pair of open-end slots 36s disposed respectively at opposite ends for receiving mounting screws.
  • the bracket 36- is provided with a pairof spaced upwardly extending tangs 36f disposed respectively adjacent opposite sides and effective in conjunction with the riser portion 360 to prevent the body 40 from twisting relative to the mounting platform portion 36a. Between the tangs 36f the bracket 36 is provided with a downwardly extending T-shaped tongue 363 having a head portion 36h.
  • the support plate 38 is generally rectangular and is provided with a pair of holes 38a (FIG. 5) for receiving mounting screws, a corner recess 38b for accommodating a portion of the bracket 14, and an open-end slot 380 for receiving the tongue 363.
  • the support plate 38 of the connector kit is placed on top of the neutral bar 17 with the two holes 38a aligned respectively with the holes for the two rightmost screws 27, and the two rightmost screws 27 are then replaced to secure the support plate 38 on the neutral bar 17 with the recess 38b adjacent the bracket 14 and the slot 38c facing outwardly.
  • the third, fourth, and fifth rightmost screws 26 are then removed from the neutral bar 18, and the mounting bracket 36 of the connector kit with the connector body 40 secured thereto by the screw 44 is mounted with the tongue 36g in the slot 380, the head portion 36h below the support plate 38, the fastening portion 36d on top of the neutral bar 18, and the slots 36e aligned respectively with the holes for the third and fifth rightmost screws 26.
  • Two screws 26 without the spring clip clamping shoes 25 are then replaced in the third and fifth rightmost holes to secure the mounting bracket 36 in place.
  • a connector kit may be installed in a similar manner on the left side of the connector body 28 as viewed in FIG. 1.
  • the connector kits are readily and rigidly securable in the field to the neutral bar assembly of an existing panelboard to enable acceptance of larger wires than can be accommodated by the neutral bars 17, 18, 19, and 20.
  • the cooperation between the support plate 38 and the tongue 36g greatly strengthens the mounting of the mounting bracket 36 on the neutral bar 18, and the screw 42 of each connecter kit may be tightened with a high torque to clamp a wire tightly without fear of twisting the connector kit off the neutral bar assembly.
  • a connector kit securable in the field to a stepped pair of upper and lower neutral bars of a neutral bar assembly of an existing electrical panelboard comprising a support plate secured to the lower neutral bar after installation of the kit, a stepped mounting bracket having a fastening portion secured to the upper neutral bar after installation of the kit, a mounting platform portion disposed between the fastening portion and the support plate after installation of the kit, a riser portion connecting the mounting platform portion and the fastening portion, and a depending tongue portion extending downwardly from the mounting platform portion and interlocked with the support plate after installation of the kit, a connector body secured to the mounting platform portion after installation of the kit, and a clamping screw threadly engaged with the connector body after installation of the kit.
  • a connector kit as claimed in claim 1 including a mounting screw securing the connector body to the mounting platform portion after installation of the kit.

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  • Installation Of Indoor Wiring (AREA)

Abstract

A connector kit attachable in the field to an existing neutral bar assembly to enable larger wires to be connected thereto than it was originally designed to accept.

Description

United States Patent Brumfield 154] CONNECTOR KIT ATTACHABLE TO EXISTING NEUTRAL BAR ASSEMBLY [72] Inventor: Walter T. Brumfleld, Nicholasville,
[73] Assignee: Square D Company, Park Ridge,
Mich.
[221 Filed: March 18, 1971 [211 App]. No.: 125,717
[52] US. Cl. .339] 198 N [51 Int. Cl. ..1101r 9/00 [58] Field of Search ..339/l98, 242, 19, 22, 272
[56] References Cited UNITED STATES PATENTS 2,909,757 10/1959 Speck ..339/198N 51 Sept. 19, 1972 3,171,708 3/1965 Salomone ..339/198 N 2,748,365 5/1956 Speck ..339/ 198 N 2,880,263 3/1959 Herrmann et a1 ..339/ 198 N 3,133,779 5/1964 Stanback ..339/242 Primary Examiner-Stephen J. Novosad Assistant Examiner--Robert A. lI-lafer Attorney-Harold J. Rathbun and Paul J. Rose ABSTRACT A connector kit attachable in the field to an existing neutral bar assembly to enable larger wires to be connected thereto than it was originally designed to accept.
5 Claims, 9 Drawing figures CONNECTOR KIT ATTACIIABLE TO EXISTING NEUTRAL BAR ASSEMBLY Electrical circuit breaker panelboards are generally designed to accept circuit breakers of a given maximum rating. With the ever increasing demand for electrical power, it is desirable to be able to install circuit breakers of a larger rating than that for which a panelboard was originally designed. This requires being able to connect larger wires to the neutral bar assembly of the panelboard than it was originally designed to accept.
An object of the invention is to provide a connector kit rigidly securable in the field to a stepped pair of neutral bars of the neutral bar assembly of an existing electrical panelboard and enabling the assembly to accept a larger wire than it was originally designed to accept, the connector kit having a good electrical connection to the assembly after installation and being able to withstand the higher clamping torque required for the larger wire.
Other objects and advantages will become apparent from the following specification considered along with the accompanying drawings in which:
FIG. 1 is a front view of a prior existing neutral bar assembly;
FIG. 2 is an end view of the prior neutral bar assembly taken from the right-hand side of FIG. 1;
FIG. 3 is a perspective view of a connector body of a connector kit constructed in accordance with the invention;
FIG. 4 is a perspective view of a stepped mounting bracket of the connector kit;
. FIG. 5 is a perspective view of a support plate of the connector kit;
FIG. 6 is a perspective view of a clamping screw of the connector kit;
FIG. 7 is a top view of a neutral bar assembly similar to the prior existing neutral bar assembly of FIGS. 1 and 2 but having a pair of the connector kits of this invention secured thereto;
FIG. 8 is a front view of the neutral bar assembly of FIG. 7; and
FIG. 9 is a fragmentary sectional view taken along the line 9-9 of FIG. 8.
With reference to the drawings, a prior existing neutral bar assembly 11 of FIGS. 1 and 2 and a modified neutral bar assembly 12 of FIGS. 7-9 having the connector kit of the invention secured thereto each include a molded plastic base 13 having a mounting bracket 14 secured thereto by a pair of screws 16 (FIG. 7) threaded into the bracket from the underside of the base and having head portions (not shown) recessed therein.
Four neutral bars 17, 18, 19, and are secured to the bracket 14 of each of the assemblies 11 and 12 respectively by pairs of screws 21, 22, 23, and 24. Each of the bars is preferably formed by the method disclosed in US. Pat. No. 3,228,094 issued Jan. I l, 1966, and if desired, the bars 18 and 20 may have spring clip clamping shoes mounted on their clamping screws 26 as shown more fully in US. Pat. No. 3,426,319 issued Feb. 4, 1969. The bars 17 and 19 are provided with clamping screws 27.
verted screw 30 which extends through a lower portion of the body 28, is threaded into the tang 14a, and extends with clearance sufficiently .into a hole in a spacer 32 in a wire receiving aperture 28a of the body 28 to prevent the spacer 32 from sliding out of the body 28. Overhanging portions 28b of the body 28 prevent the spacer 32 from rising off the screw 30. A clamping screw 34 is threaded into the body 28 to clamp the main neutral wire (not shown) of an electrical panelboard against the spacer 32. The: clamping screw 34 is provided with a hexagonal recess 34a (FIG. 7) for receiving a hexagonal socket wrench.
The connector kit of this invention includes a stepped mounting bracket 36 best shown in FIG. 4, a support plate 38 best shown in FIG. 5, a connector body 40 best shown in FIG. 3, a clamping screw 42 best shown in FIG. 6, and a mounting screw 44 (FIG. 9). In the embodiment shown, two of the connector kits are mounted on the neutral bar assembly 12 as shown in FIGS. 7-9.
Each bracket 36 includes a generally square mounting platform portion 36a having a central threaded hole 36b extending therethrough. Each connector body 40 is generally in the shape of a square prism and has a hole 40a extending therethrough from front to back for receiving a wire conductor and a threaded hole 40b (FIG. 9) extending from the top into intersecting rela tionship with the hole 40a for receiving the respective clamping screw 42. Each clamping screw 42 is provided with a hexagonal recess 42a (FIG. 7) for receiving a hexagonal socket wrench. At the bottom of the body 40 a hole 40c aligned with but of smaller diameter than the hole 40b is provided for receiving the mounting screw 44. The hole 400 is enlarged at its upper end to accommodate an enlarged head portion of the screw 44. The screw 44 is threaded into the hole 36b to secure the body 40 to the platform portion 36a.
At the rear of the mounting platform portion 360 the bracket 36 is provided with a riser portion 36c (FIG. 4) leading to a fastening portion 36d parallel with the platform portion 36a and having a pair of open-end slots 36s disposed respectively at opposite ends for receiving mounting screws.
At the front of the mounting platform portion 360, the bracket 36-is provided with a pairof spaced upwardly extending tangs 36f disposed respectively adjacent opposite sides and effective in conjunction with the riser portion 360 to prevent the body 40 from twisting relative to the mounting platform portion 36a. Between the tangs 36f the bracket 36 is provided with a downwardly extending T-shaped tongue 363 having a head portion 36h.
The support plate 38 is generally rectangular and is provided with a pair of holes 38a (FIG. 5) for receiving mounting screws, a corner recess 38b for accommodating a portion of the bracket 14, and an open-end slot 380 for receiving the tongue 363.
To install a connector kit on the right side, for example, of the connector body 28 as viewed in FIG. 1, the three rightmost screws 27 are removed from the neutral bar 17, the support plate 38 of the connector kit is placed on top of the neutral bar 17 with the two holes 38a aligned respectively with the holes for the two rightmost screws 27, and the two rightmost screws 27 are then replaced to secure the support plate 38 on the neutral bar 17 with the recess 38b adjacent the bracket 14 and the slot 38c facing outwardly. The third, fourth, and fifth rightmost screws 26 are then removed from the neutral bar 18, and the mounting bracket 36 of the connector kit with the connector body 40 secured thereto by the screw 44 is mounted with the tongue 36g in the slot 380, the head portion 36h below the support plate 38, the fastening portion 36d on top of the neutral bar 18, and the slots 36e aligned respectively with the holes for the third and fifth rightmost screws 26. Two screws 26 without the spring clip clamping shoes 25 are then replaced in the third and fifth rightmost holes to secure the mounting bracket 36 in place.
A connector kit may be installed in a similar manner on the left side of the connector body 28 as viewed in FIG. 1.
The connector kits are readily and rigidly securable in the field to the neutral bar assembly of an existing panelboard to enable acceptance of larger wires than can be accommodated by the neutral bars 17, 18, 19, and 20. The cooperation between the support plate 38 and the tongue 36g greatly strengthens the mounting of the mounting bracket 36 on the neutral bar 18, and the screw 42 of each connecter kit may be tightened with a high torque to clamp a wire tightly without fear of twisting the connector kit off the neutral bar assembly.
lclaim:
l. A connector kit securable in the field to a stepped pair of upper and lower neutral bars of a neutral bar assembly of an existing electrical panelboard, the kit comprising a support plate secured to the lower neutral bar after installation of the kit, a stepped mounting bracket having a fastening portion secured to the upper neutral bar after installation of the kit, a mounting platform portion disposed between the fastening portion and the support plate after installation of the kit, a riser portion connecting the mounting platform portion and the fastening portion, and a depending tongue portion extending downwardly from the mounting platform portion and interlocked with the support plate after installation of the kit, a connector body secured to the mounting platform portion after installation of the kit, and a clamping screw threadly engaged with the connector body after installation of the kit.
2. A connector kit as claimed in claim 1 including a mounting screw securing the connector body to the mounting platform portion after installation of the kit.
3. A connector kit as claimed in claim 1 wherein the mounting platform portion is provided with a pair of upwardly extending tangs disposed oppositely from the riser portion and respectively on opposite sides of the tongue portion.
4. A connector kit as claimed in claim 1 wherein the support plate is provided with an open-end slot receiving the tongue portion after installation of the kit.
5. A connector kit as claimed in claim 1 wherein the tongue portion is T-shaped and has a head portion disposed on the opposite side of the support plate from the mounting platform portion after installation of the kit.

Claims (5)

1. A connector kit securable in the field to a stepped pair of upper and lower neutral bars of a neutral bar assembly of an existing electrical panelboard, the kit comprising a support plate secured to the lower neutral bar after installation of the kit, a stepped mounting bracket having a fastening portion secured to the upper neutral bar after installation of the kit, a mounting platform portion disposed between the fastening portion and the support plate after installation of the kit, a riser portion connecting the mounting platform portion and the fastening portion, and a depending tongue portion extending downwardly from the mounting platform portion and interlocked with the support plate after installation of the kit, a connector body secured to the mounting platform portion after installation of the kit, and a clamping screw threadly engaged with the connector body after installation of the kit.
2. A connector kit as claimed in claim 1 including a mounting screw securing the connector body to the mounting platform portion after installation of the kit.
3. A connector kit as claimed in claim 1 wherein the mounting platform portion is provided with a pair of upwardly extending tangs disposed oppositely from the riser portion and respectively on opposite sides of the tongue portion.
4. A connector kit as claimed in claim 1 wherein the support plate is provided with an open-end slot receiving the tongue portion after installation of the kit.
5. A connector kit as claimed in claim 1 wherein the tongue portion is T-shaped and has a head portion disposed on the opposite side of the support plate from the mounting platform portion after installation of the kit.
US125717A 1971-03-18 1971-03-18 Connector kit attachable to existing neutral bar assembly Expired - Lifetime US3693137A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4722701A (en) * 1986-09-29 1988-02-02 Todd Engineering Sales, Inc. Fuse block for miniature plug-in blade-type fuse
US5032092A (en) * 1989-12-22 1991-07-16 Connection Designs Corporation Power distribution block
US5244423A (en) * 1992-04-29 1993-09-14 Boltswitch, Inc. Turn prevention assembly for electrical connection lugs
US5322458A (en) * 1991-09-26 1994-06-21 Wago Verwaltungsgesellschaft Mbh Collective conenction device for wire conductors
WO1995034107A1 (en) * 1994-06-03 1995-12-14 Square D Company Neutral lug assembly for a panelboard
US20100178813A1 (en) * 2009-01-13 2010-07-15 Gm Global Technology Operations, Inc. Low inductance busbar assembly

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2748365A (en) * 1952-08-30 1956-05-29 Westinghouse Electric Corp Neutral bar assembly
US2880263A (en) * 1956-12-28 1959-03-31 Ite Circuit Breaker Ltd Narrow panelboard having suspended main lugs
US2909757A (en) * 1952-08-30 1959-10-20 Westinghouse Electric Corp Neutral bar assembly
US3133779A (en) * 1962-06-12 1964-05-19 Square D Co Neutral wire connector
US3171708A (en) * 1962-06-29 1965-03-02 Gen Electric Adapter for neutral terminal bar

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2748365A (en) * 1952-08-30 1956-05-29 Westinghouse Electric Corp Neutral bar assembly
US2909757A (en) * 1952-08-30 1959-10-20 Westinghouse Electric Corp Neutral bar assembly
US2880263A (en) * 1956-12-28 1959-03-31 Ite Circuit Breaker Ltd Narrow panelboard having suspended main lugs
US3133779A (en) * 1962-06-12 1964-05-19 Square D Co Neutral wire connector
US3171708A (en) * 1962-06-29 1965-03-02 Gen Electric Adapter for neutral terminal bar

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4722701A (en) * 1986-09-29 1988-02-02 Todd Engineering Sales, Inc. Fuse block for miniature plug-in blade-type fuse
US5032092A (en) * 1989-12-22 1991-07-16 Connection Designs Corporation Power distribution block
US5322458A (en) * 1991-09-26 1994-06-21 Wago Verwaltungsgesellschaft Mbh Collective conenction device for wire conductors
US5244423A (en) * 1992-04-29 1993-09-14 Boltswitch, Inc. Turn prevention assembly for electrical connection lugs
WO1995034107A1 (en) * 1994-06-03 1995-12-14 Square D Company Neutral lug assembly for a panelboard
US5531617A (en) * 1994-06-03 1996-07-02 Square D Company Neutral lug assembly for a panelboard
US20100178813A1 (en) * 2009-01-13 2010-07-15 Gm Global Technology Operations, Inc. Low inductance busbar assembly
US7798833B2 (en) * 2009-01-13 2010-09-21 Gm Global Technology Operations, Inc. Low inductance busbar assembly

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