Circuit breakers with shaped neutral busbars and/or load terminals and related methods

Patent metadata

Field	Value
Publication number	US-11322328-B2
Application number	US-201816014574-A
Country	US
Kind code	B2
Filing date	Jun 21, 2018
Priority date	Apr 20, 2016
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Arc Fault Circuit Interrupter (AFCI), Ground Fault Circuit Interrupter (GFCI) or AF/GF circuit breakers which may optionally have relatively small or compact bodies that have shaped neutral busbars and/or load terminals with an arm that extends through a window of a current transformer in a circuit breaker housing. The neutral busbar and/or load terminal can have a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that extends behind the first segment about a printed circuit board. A plug-on, pigtail or bolt-on neutral can engage an electrical pad of the neutral busbar.

First claim

That which is claimed is:

1. A circuit breaker, comprising:
a circuit breaker housing, wherein the circuit breaker housing comprises a bottom base with an inner surface with an inwardly projecting segment shaped with a curved cavity;
a current transformer, the current transformer comprising a window extending therethrough, wherein the current transformer is held in the curved cavity adjacent a load side of the circuit breaker housing;
a printed circuit board (PCB) in the circuit breaker housing; and
a load terminal in the circuit breaker housing, wherein the load terminal has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that laterally extends behind the first segment adjacent to and behind the window, wherein the second segment terminates at an internal free end that extends toward an operator handle, and wherein the second segment is attached to a wire that connects to a trip mechanism in the circuit breaker housing.

2. The circuit breaker of claim 1 , wherein the inwardly projecting segment shaped with the curved cavity is defined by an arcuate surface extending between laterally spaced apart inwardly projecting wall segments, and wherein the laterally spaced apart inwardly projecting wall segments terminate under the PCB in the circuit breaker housing.

3. The circuit breaker of claim 2 , wherein the curved cavity has a radius of curvature that corresponds to an outer radius of the current transformer.

4. The circuit breaker of claim 1 , wherein the load terminal is a unitary monolithic shaped member.

5. The circuit breaker of claim 1 , wherein the circuit breaker is an Arc Fault (AF) Circuit Interrupter (AFCI) circuit breaker, a Ground Fault (GF) Circuit Interrupter (GFCI) circuit breaker, or an AF/GF circuit breaker.

6. The circuit breaker of claim 1 , wherein the circuit breaker further comprises a neutral busbar in the circuit breaker housing, wherein the neutral busbar has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that extends behind the first segment, and wherein the neutral busbar second segment has connectors/connector features that directly engage mating connectors/connector features on the PCB to electrically connect and fixedly attach the neutral busbar to the PCB without requiring welding.

7. The circuit breaker of claim 6 , wherein the first segment of the neutral busbar has a straight planar arm with a first width that merges into an outer free end.

8. The circuit breaker of claim 6 , wherein the connectors/connector features of the PCB are female connectors.

9. The circuit breaker of claim 6 , wherein the first segment of the neutral busbar has a length L 1 that is greater than a length L 2 of the second segment of the neutral busbar, wherein the first segment of the neutral busbar has a planar arm with a primary surface that is orthogonal to a plane of a primary surface of the PCB, and wherein the second segment of the neutral busbar has a straight bridging arm that resides above neutral busbar connection/connector features on the PCB.

10. A circuit breaker, comprising:
a circuit breaker housing;
a current transformer in the circuit breaker housing, the current transformer comprising a window extending therethrough;
a printed circuit board (PCB) in the circuit breaker housing, wherein the PCB has a primary surface that extends laterally and longitudinally in the housing, and wherein the current transformer is positioned in the circuit breaker housing to extend above and below the primary surface of the PCB;
a load terminal in the circuit breaker housing, wherein the load terminal has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that laterally extends behind the first segment attached to a wire that connects to a trip mechanism in the circuit breaker housing; and
a neutral busbar in the circuit breaker housing, wherein the neutral busbar has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that extends behind the first segment, and wherein the second segment of the neutral busbar has connectors/connector features that directly engage mating connectors/connector features on the PCB to electrically connect and fixedly attach the neutral busbar to the PCB without requiring welding, wherein the second segment of the neutral busbar comprises a planar pad that is parallel to a plane of the primary surface of the PCB and that resides closer to a front of the circuit breaker housing at a load side of the circuit breaker than a laterally extending arm of the second segment of the neutral busbar, and wherein an internal end portion of a pigtail neutral is configured to engage the planar pad.

11. A circuit breaker, comprising:
a circuit breaker housing;
a current transformer in the circuit breaker housing, the current transformer comprising a window extending therethrough;
a printed circuit board (PCB) in the circuit breaker housing; and
a load terminal in the circuit breaker housing, wherein the load terminal has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that laterally extends behind the first segment attached to a wire that connects to a trip mechanism in the circuit breaker housing,
wherein the circuit breaker housing comprises a bottom base member with an internal facing curved cavity, a cooperating middle base member, and a cooperating top cover that attach together, wherein the middle base member holds the PCB over the bottom base member and inside the top cover, and wherein the internal facing curved cavity holds the current transformer under a window in the middle base member adjacent a load side of the circuit breaker with the portion of the window of the current transformer above a recessed segment of the PCB and a portion of the window of the current transformer below the recessed segment of the PCB.

12. A circuit breaker, comprising:
a circuit breaker housing;
a current transformer in the circuit breaker housing, the current transformer comprising a window;
a printed circuit board (PCB) in the circuit breaker housing; and
a neutral busbar in the circuit breaker housing, wherein the neutral busbar has a rigid or semi-rigid shaped body with a first segment that extends through the window of the current transformer and a second segment that extends behind the first segment and is attached to the PCB, and wherein the neutral busbar comprises male connector features that engage female connectors held on the PCB,
wherein the circuit breaker housing comprises a bottom base member with an internal facing curved cavity, a cooperating middle base member, and a cooperating top cover that attach together, wherein the middle base member holds the PCB over the bottom base member and inside the top cover, and wherein the internal facing curved cavity holds the current transformer adjacent a load side of the circuit breaker with a portion of the window above the PCB and a portion of the window below the PCB.

13. The circuit breaker of claim 1 , wherein the free end has a greater width than the first segment and at least part of the second segment.

14. The circuit breaker of claim 6 , wherein the connectors/connector features of the PCB and neutral busbar are plug-in and/or press-fit connectors/connector features.

15. A circuit breaker, comprising:
a circuit bre

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Hiremath Somashekharayya
• Jimenez Sandy Omar

Classifications

• H01H83/144 Primary

  with differential transformer · CPC title

• H01H23/006

  adapted for connection with printed circuit boards · CPC title

• H01H2083/148

  with primary windings formed of rigid copper conductors · CPC title

• H01H69/00

  Apparatus or processes for the manufacture of emergency protective devices · CPC title

• H01F38/20

  Instruments transformers · CPC title