Plug-on neutral load center having a rotating neutral rail retained by a two-piece dielectric barrier

Patent metadata

Field	Value
Publication number	US-8953306-B2
Application number	US-201213720163-A
Country	US
Kind code	B2
Filing date	Dec 19, 2012
Priority date	Dec 19, 2012
Publication date	Feb 10, 2015
Grant date	Feb 10, 2015

Abstract

A load center featuring a two-piece dielectric barrier that securely retains a plug-on neutral rail and methods of assembling the same. The barrier includes a shield and a base having a protrusion that cooperates with fingers of the shield to securely retain the conductor in the load center. The shield is installed over the base and rests on hooks protruding from the base. This creates a distance between the protrusion and the fingers to allow the conductor to be inserted through a gap between the fingers along the conductor's skinny edge. The conductor rotates 90 degrees until it rests on the protrusion. The base and shield are snapped together, causing the hooks of the base to attach to the shield. At the same time, the fingers of the base move downward to rest against the conductor so that it is sandwiched securely between the protrusion and the fingers.

First claim

What is claimed is:

1. An electrical distribution apparatus, comprising:
a fixed dielectric base having a major surface defining a plane and a protrusion extending away from the plane along a z-axis orthogonal to the plane;
a separate dielectric shield member having opposing retention features positioned a distance from the plane along the z-axis and from the protrusion, the retention features forming a gap therebetween; and
an elongate plug-on neutral rail having a cross section whose first dimension is smaller than a second dimension orthogonal to the first dimension,
wherein a width of the gap is larger than the first dimension but smaller than the second dimension.

2. The apparatus of claim 1 , wherein a distance between the protrusion and the retention features is smaller than the second dimension when the base is installed relative to the shield member.

3. The apparatus of claim 1 , wherein the plug-on neutral rail is configured to be inserted through the gap along the first dimension but is retained by the retention features of the shield member against the protrusion along the second dimension.

4. The apparatus of claim 1 , further comprising an enclosure into which the base, the shield member, and the neutral rail are installed.

5. The apparatus of claim 1 , wherein the neutral rail is configured to receive a plug-on neutral connector of a circuit breaker, the plug-on neutral connector being configured to connect the circuit breaker to neutral current distributed by the apparatus.

6. The apparatus of claim 1 , wherein the cross section of the neutral rail is generally oval or rounded rectangular and has the same cross section across an entire length of the neutral rail.

7. The apparatus of claim 1 , wherein the cross section of the neutral rail is generally oblong.

8. The apparatus of claim 1 , wherein the neutral rail includes aluminum or copper and is elongate, and wherein the apparatus is a loadcenter.

9. The apparatus of claim 1 , further comprising a neutral connector mechanically and electrically connecting the neutral rail to a neutral busbar of the apparatus, the neutral busbar being configured to connect the apparatus to a neutral electrical current corresponding to a power source external to the apparatus.

10. The apparatus of claim 9 , wherein the neutral connector includes a rail retention feature configured to retain the neutral rail in the rail retention feature, and a connector feature configured to connect to the neutral busbar.

11. The apparatus of claim 10 , wherein the rail retention feature of the neutral connector is enclosed and has an opening through which an end of the neutral rail is received, and the connector feature includes a tab having an aperture configured to receive a fastener that fastens the tab of the neutral connector to the neutral busbar.

12. The apparatus of claim 1 , wherein each of the opposing retention features includes a finger member having a corresponding inner surface whose shape conforms to an edge portion of the neutral rail when installed against the protrusion to retain the neutral rail securely between the shield member and the base.

13. The apparatus of claim 1 , wherein the opposing retention features is a plurality of opposing retention features that are disposed along a length of the shield member at a spacing corresponding to at least a width of a circuit breaker installed onto the neutral rail, and wherein the protrusion extends along substantially the entirety of the length of the shield member.

14. An electrical distribution apparatus, comprising:
a rear wall defining a plane;
a dielectric substrate having a major surface parallel with the plane;
a dielectric shield member;
a retention feature extending away from the plane along a z-axis;
a gap defined by at least the retention feature on one side;
a support member below the gap along the z-axis; and
a plug-on neutral rail, a part of which has a width dimension that is larger than a width of the gap, wherein the part of the plug-on neutral rail is received through the gap in a direction along the z-axis and is retained at least by the retention feature against the support.

15. The apparatus of claim 14 , wherein the retention feature is a pair of retention features defining the gap, the retention features having a curved upper portion that cause the retention features to bend toward one another.

16. The apparatus of claim 15 , wherein the neutral rail has a cross section that has a generally round portion along a length of the neutral rail and a flattened bottom portion that abuts against the support member when the neutral rail is retained by the retention features.

17. The apparatus of claim 15 , wherein the cross section includes rounded bottom edges on either side of the flattened bottom portion such that the rounded bottom edges engage the retention features as the neutral rail is inserted in a direction along the z-axis through the gap.

18. The apparatus of claim 14 , wherein the retention feature is integrally formed with the dielectric shield member.

19. The apparatus of claim 15 , wherein the retention features are snap fingers such that each of the curved upper portions forms a snap fit clip portion that engages corresponding side flat surfaces of the neutral rail, the neutral rail having a bottom flat surface that rests against the support and a top portion extending along the z-axis away from the corresponding side flat surfaces, the top portion being configured to receive thereon a plug-on neutral connector of a circuit breaker.

20. The apparatus of claim 19 , wherein the side flat surfaces contribute to the width dimension of the neutral rail.

21. The apparatus of claim 14 , wherein the retention feature has a sufficient flexibility and stiffness to allow the retention feature to flex from an unstressed position and thereby widen the gap enough to allow the neutral rail to be inserted through the gap and to return to the unstressed position in response to the neutral rail clearing the gap.

22. The apparatus of claim 14 , wherein the dielectric shield member includes the retention feature, wherein the dielectric substrate has a second retention feature, and wherein the retention feature and the second retention feature form the gap.

23. The apparatus of claim 21 , wherein the retention feature includes a curved surface configured to mate with a first curved surface portion of the neutral rail, and wherein the second retention feature includes a curved surface configured to mate with a second curved surface portion of the neutral rail.

24. The apparatus of claim 23 , wherein the neutral rail is a round bar with a round cross section along the entire length of the neutral rail, the neutral rail having an exposed surface portion configured to receive thereon a plug-on neutral connector of a circuit breaker.

Assignees

• Schneider Electric Usa Inc

Inventors

• Wheeler Kim D
• Sharp Jeffrey O
• Potratz Jason D

Classifications

• H02B1/20 Primary

  Bus-bar or other wiring layouts, e.g. in cubicles, in switchyards (installations of bus-bars H02G5/00) · CPC title

• H02B1/056

  Mounting on plugboards · CPC title