Interrupter assembly for a circuit breaker

• US 20060017531A1
• Filed: 07/21/2004
• Published: 01/26/2006
• Est. Priority Date: 07/21/2004
• Status: Active Grant

• Current Assignee: Hitachi Energy Limited (Hitachi, Ltd.)
• Original Assignee: ABB Incorporated (ABB Limited)
• Inventors: Eley, Edgar R., Still, Robert L. Jr.
• Granted Patent: US 7,154,061 B2
• Time in Patent Office: Days
• US Class Current: 335/16
• CPC Class Codes: H01H 1/2066 Fork-shaped bridge; Two transversally connected contact arms bridging two fixed contacts
• CPC Class Codes: H01H 33/68 Liquid-break switches, e.g. oil-break
• CPC Class Codes: H01H 73/18 Means for extinguishing or suppressing arc magnet coil acting as blow-out device H01H71/38
• CPC Class Codes: H01H 9/34 Stationary parts for restricting or subdividing the arc, e.g. barrier plate

Abstract

A preferred embodiment of an interrupter assembly for a circuit breaker includes a first contact, a conductor, and a second contact mounted on the conductor. The second contact and the conductor are movable in relation to the first contact between a first position wherein the first and the second contacts are in electrical contact, and a second position. The interrupter assembly also includes a body having a first and a second half each having a plurality of recesses formed therein. The recesses form chambers within the body for holding insulating fluid when the first and the second halves are mated. The body receives the second contact and the conductor so that the conductor and the second contact are drawn through the chambers as the second contact moves from the first to the second position.

Claims

1. An interrupter assembly for a circuit breaker, comprising:

a first and a second stationary contact;

a moving contact assembly comprising a substantially U-shaped conductor, a first moving contact mounted on a first end of the conductor, and a second moving contact mounted on a second end of the conductor, the moving contact assembly being movable between a first position wherein the first and second moving contacts are in electrical contact with the respective first and second stationary contacts, and a second position wherein the first and second moving contacts are electrically isolated from the respective first and second stationary contacts; and

a body having a first and a second half each having a plurality of recesses formed therein, wherein the recesses formed in the first half face corresponding ones of the recesses formed in the second half to form chambers for holding insulating fluid when the first and the second halves are mated, the first and second halves each comprise a plurality of ribs, each of the ribs has a recess formed therein for receiving a corresponding one of the first and second moving contacts, each of the ribs of the first half faces a corresponding one of the ribs of the second half when the first and second halves are mated so that ribs encircle the first and second moving contacts and substantially isolate adjacent ones of the chambers, and the body receives the moving contact assembly so that the first and the second moving contacts are drawn through respective ones of the chambers and the ribs as the moving contact assembly moves from the first to the second position.

2. The interrupter assembly of claim 1, wherein each of the recesses is defined at least in part by a substantially curvilinear surface of one of the first and second halves.

3. The interrupter assembly of claim 1, wherein the chambers are substantially cylindrical.

4. The interrupter assembly of claim 1, wherein the first and second stationary contacts each have a bore formed therein for receiving the respective first and second moving contacts.

5. The interrupter assembly of claim 1, wherein the conductor comprises a first leg, a second leg adjoining the first leg, and a third leg adjoining the second leg, the first and third legs being of substantially equal length and being substantially perpendicular to the second leg.

6. The interrupter assembly of claim 1, wherein a first electric arc forms between the first moving contact and the first stationary contact, and a second electric arc forms between the second moving contact and the second stationary contact as the moving contact assembly moves from the first to the second position;

and the first and the second arcs are drawn through respective ones of the chambers so that the first and the second arcs are extinguished by the insulating fluid.

7. The interrupter assembly of claim 6, wherein the first and the second moving contacts are drawn successively through adjacent ones of the respective chambers.

8. The interrupter assembly of claim 6, wherein the insulating fluid in each of the chambers is substantially isolated from the insulating fluid in adjacent ones of the chambers.

32. The interrupter assembly of claim 1, wherein each of the ribs is semi-circular and each of the recesses ribs is semi-circular.

33. The interrupter assembly of claim 32, wherein the recesses are sized so that the first and second moving contacts fit snugly within the recesses.

34. The interrupter assembly of claim 1, wherein the each of the ribs has a substantially planar upper surface and a substantially planar lower surface.

35. The interrupter assembly of claim 34, wherein the upper surface of each of the ribs forms a lower end of one of the chambers, and the lower surface of each of the ribs forms an upper end of another one of the chambers.

36. The interrupter assembly of claim 34, wherein each of the ribs includes an edge adjoining the upper and lower surfaces of the rib, and the edges of the ribs of the first half each abut an edge of a corresponding one of the ribs of the second half when the first and the second halves are mated.

37. The interrupter assembly of claim 1, wherein corresponding ones of the ribs of the first and the second halves are symmetrically disposed around the first and second moving contacts.

9-11. -11. (canceled)

12. An interrupter assembly for a circuit breaker, comprising a first and a second stationary contact, and a moving contact assembly comprising:

a conductor having a first leg, a second leg adjoining the first leg, and a third leg adjoining the second leg, the first and third legs being substantially perpendicular to the second leg and having substantially the same length so that the conductor is substantially U-shaped;

a first moving contact mounted on the first leg;

a second moving contact mounted on the second leg, the moving contact assembly being movable between a first position wherein the first and the second moving contacts electrically and mechanically contact the respective first and second stationary contacts, and a second position wherein the first and second moving contacts are electrically isolated from the respective first and second stationary contacts; and

a body for housing the moving contact assembly and the stationary contacts, wherein the body has a first and a second half each having a plurality of recesses formed therein, the recesses formed in the first half face corresponding ones of the recesses formed in the second half to form chambers for holding insulating fluid when the first and the second halves are mated, the first and the second halves each have a plurality of semi-circular ribs formed therein, the ribs of the first half each face a corresponding one of the ribs of the second half when the first and second halves are mated so that the corresponding ribs of the first and second halves define upper and lower boundaries of the chambers and encircle the first and the second moving contacts whereby the ribs substantially isolate adjacent ones of the chambers.

13. The interrupter assembly of claim 12, wherein the substantial U shape of the conductor causes the first moving contact and the second contact to separate from the respective first and second stationary contacts on a substantially simultaneous basis as the moving contact assembly moves from the first to the second position.

14-15. -15. (canceled)

16. An interrupter assembly for a circuit breaker, comprising:

a first contact;

a conductor;

a second contact mounted on the conductor, the second contact and the conductor being movable in relation to the first contact between a first position wherein the first and the second contacts are in electrical contact, and a second position; and

a body having a first and a second half each having a plurality of recesses formed therein, the recesses forming chambers within the body for holding insulating fluid when the first and the second halves are mated, the first and second halves of the body each comprising a plurality of ribs each having a substantially planar first surface that partially defines one of the chambers, and a substantially planar second surface that partially defines an adjacent one of the chambers, the body receiving the second contact and the conductor so that the conductor and the second contact are drawn through the chambers as the second contact moves from the first to the second position.

17. The interrupter assembly of claim 16, wherein each of the recesses is defined at least in part by a substantially curvilinear surface of one of the first and the second halves.

18. The interrupter assembly of claim 16, wherein the chambers are substantially cylindrical.

19. The interrupter assembly of claim 16, wherein an electric arc forms between the first and the second contacts as the conductor and the second contact move from the first to the second position, and the arc is drawn through the chambers so that the arc is extinguished by the insulating fluid.

20. The interrupter assembly of claim 16, wherein the second contact is drawn successively through adjacent ones of the chambers.

21. The interrupter assembly of claim 16, wherein the insulating fluid in each of the chambers is substantially isolated from the insulating fluid in adjacent ones of the chambers.

25. The interrupter assembly of claim 19, wherein the electric arc is drawn through the chambers and extinguished by the insulating fluid.

26. The interrupter assembly of claim 16, further comprising a third contact, wherein the conductor is substantially U-shaped and the first and the third contacts are mounted on opposing ends of the conductor.

22-24. -24. (canceled)

28. An interrupter assembly for a circuit breaker, comprising:

a first contact;

a conductor;

a second contact mounted on the conductor, the second contact and the conductor being movable in relation to the first contact between a first position wherein the first and the second contacts are in electrical contact, and a second position wherein the second contact is electrically isolated from the first contact; and

a body for receiving the first and the second contacts and the conductor, wherein the body comprises a first and a second half, the body has a plurality of chambers formed therein for holding insulating fluid;

each chamber is defined by a recess formed in the first half, and a corresponding recess formed in the second half that adjoins the recess formed in the first half when the first and second halves are mated;

the chambers are further defined by ribs formed in the first and second halves, each of the ribs of the first half faces a corresponding rib formed in the second half when the first and second halves are mated so that the corresponding ribs of the first and second halves are symmetrically disposed around the moving contact; and

the second contact is drawn through the chambers when the second contact moves from the first to the second position.

29. The interrupter assembly of claim 28, further comprising a third contact, wherein the conductor is substantially U-shaped and the first and the third contacts are mounted on opposing ends of the conductor.

30. (canceled)

31. A circuit breaker, comprising:

an interrupter assembly comprising;

a first and a second stationary contact;

a moving contact assembly comprising a substantially U-shaped conductor, a first moving contact mounted on a first end of the conductor, and a second moving contact mounted on a second end of the conductor, the moving contact assembly being movable between a first position herein the first and second moving contacts are in electrical contact with the respective first and second stationary contacts, and a second position wherein the first and second moving contacts are electrically isolated from the respective first and second stationary contacts; and

a body having a first and a second half each having a plurality of recesses formed therein, wherein the recesses formed in the first half face corresponding ones of the recesses formed in the second half to form chambers for holding insulating fluid when the first and the second halves are mated, the first and second halves each comprise a plurality of ribs, each of the ribs has a recess formed therein for receiving a corresponding one of the first and second moving contacts, each of the ribs of the first half faces a corresponding one of the ribs of the second half when the first and second halves are mated so that ribs encircle the first and second moving contacts and substantially isolate adjacent ones of the chambers, and the body receives the moving contact assembly so that the first and the second moving contacts are drawn through respective ones of the chambers and the ribs as the moving contact assembly moves from the first to the second position;

an actuator assembly for moving the moving contact assembly from the first to the second position, comprising a contact arm mechanically coupled to the conductor, and a spring for biasing the contact arm; and

a current sensor assembly for activating the actuator mechanism in response to over-temperature and over-current conditions.