DC electrical circuit breaker

Patent metadata

Field	Value
Publication number	US-10176945-B2
Application number	US-201715471237-A
Country	US
Kind code	B2
Filing date	Mar 28, 2017
Priority date	Apr 15, 2016
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

A DC electrical circuit breaker includes first and second movable electrical contacts. The circuit breaker includes a magnetic circuit including a magnet and generating a magnetic field able to guide an electrical arc in the direction of a quenching chamber, and having for this purpose curved field lines extending perpendicularly to opposite lateral walls of an electrical arc formation chamber, these field lines converging, in a central region of the arc formation chamber containing the contact zones, toward the quenching chamber while extending parallel to the longitudinal plane.

First claim

The invention claimed is:

1. A DC electrical circuit breaker, comprising:
first and second terminals for a DC electric current,
first and second electrical contacts, connected respectively to the first and second terminals and being selectively displaceable with respect to one another, along a longitudinal plane of the circuit breaker, between:
a closed position, in which respective contact zones of the first and second electrical contacts are in contact with one another and being configured to permit flow of the DC electric current between the first and second electrical contacts, and
an open position, in which the respective contact zones are remote from one another;

an electric arc formation chamber, in which the contact zones are disposed;
an electric arc quenching chamber; and
a magnetic circuit comprising a magnet, and a magnetic core extending at least partly along the first electrical contact, the magnetic circuit generating a magnetic field configured to guide, in a direction of the electric arc quenching chamber, an electric arc formed between the contact zones in the open position, the magnetic field having curved field lines extending essentially perpendicularly to opposite lateral walls of the electric arc formation chamber, the lateral walls being disposed on either side of the contact zones and being essentially parallel to the longitudinal plane, the curved field lines converging, at a level of a central region of the electric arc formation chamber containing the contact zones, towards the electric arc quenching chamber while extending parallel to the longitudinal plane.

2. The circuit breaker according to claim 1 , wherein the magnetic core is made of a ferromagnetic material, the magnet being placed at one of the ends of the magnetic core.

3. The circuit breaker according to claim 2 , wherein the magnet exhibits a magnetic axis oriented parallel to a longitudinal direction contained in the longitudinal plane.

4. The circuit breaker according to claim 3 , wherein a spacing between the magnet and the one of the ends of the magnetic core is less than or equal to 2 mm.

5. The circuit breaker according to claim 1 , wherein the magnet is a permanent magnet.

6. The circuit breaker according to claim 1 , wherein the magnet is made of a synthetic alloy containing a rare earth element.

7. The circuit breaker according to claim 1 , wherein the magnet is configured to generate a magnetic field of greater than or equal to 0.5 tesla.

8. The circuit breaker according to claim 1 , wherein the magnetic core is made of steel or iron.

9. The circuit breaker according to claim 1 , wherein the lateral walls are made of a ferromagnetic material.

10. The circuit breaker according to claim 3 , wherein a spacing between the magnet and the one of the ends of the magnetic core is less than or equal to 1 mm.

11. The circuit breaker according to claim 1 , wherein the magnet is made of a samarium-cobalt alloy.

12. The circuit breaker according to claim 1 , wherein the magnet is configured to generate a magnetic field of greater than or equal to 1 tesla.

13. The circuit breaker according to claim 1 , wherein the electric arc quenching chamber is disposed adjacent to and in communication with the electric arc formation chamber, such that the electric arc formation chamber extends into the electric arc quenching chamber.

14. The circuit breaker according to claim 1 , wherein the electric arc formation chamber has a prism shape with a parallelepipedal base, lateral faces of the electric arc formation chamber being formed by the opposite lateral walls.

15. A DC electrical circuit breaker, comprising:
first and second terminals for a DC electric current,
a pair of first electrical contacts respectively connected to the first and second terminals and
a pair of second electrical contacts being electrically connected to one another, each second electrical contact of the pair of second electrical contacts being selectively displaceable with respect to a corresponding first electrical contact of the pair of first electrical contacts, along a longitudinal plane of the circuit breaker, between:
a closed position, in which contact zones of said each second electrical contact and said corresponding first electrical contact are in contact with one another and are configured to permit flow of the DC electric current therebetween, and
an open position, in which the contact zones are separated from one another;

a pair of electric arc formation chambers in which the contact zones are respectively disposed;
a pair of electric arc quenching chambers, each electric arc quenching chamber of the pair of electric arc quenching chambers being disposed adjacent to a corresponding electric arc formation chamber of the pair of electric arc formation chambers; and
a pair of magnetic circuits each comprising a magnet, and a magnetic core extending at least partly along a respective first electrical contact of the pair of first electrical contacts, each magnetic circuit of the pair of magnetic circuits generating a magnetic field configured to guide, in a direction of the respective electric arc quenching chambers, electric arcs formed between the contact zones in the open position, the magnetic field having curved field lines extending essentially perpendicular to opposite lateral walls of the respective electric arc formation chambers, the lateral walls being disposed on either side of the contact zones and being essentially parallel to the longitudinal plane, the curved field lines converging, at a level of a central region of each of the electric arc formation chambers containing the respective contact zones, towards a corresponding electric arc quenching chamber of the pair of electric arc quenching chambers while extending parallel to the longitudinal plane.

Assignees

• Schneider Electric Ind Sas

Inventors

• Domejean Eric
• Rondot Loic
• Dye Stephane

Classifications

• H01H9/446

  using magnetisable elements associated with the contacts · CPC title

• H01H77/108

  comprising magnetisable elements, e.g. flux concentrator, linear slot motor · CPC title

• H01H9/36

  Metal parts · CPC title

• H01H33/08

  Stationary parts for restricting or subdividing the arc, e.g. barrier plate · CPC title

• H01H9/46

  using arcing horns (using blow-out magnet H01H9/44) · CPC title