BREAKER

• US 20110120846A1
• Filed: 11/24/2010
• Published: 05/26/2011
• Est. Priority Date: 11/24/2009
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Electric Works Company Limited (Panasonic Holdings Corporation)
• Inventors: ITO, Masahiro, YOSITANI, Katumi, URUMA, Katsuya
• Granted Patent: US 8,581,128 B2
• Time in Patent Office: Days
• US Class Current: 200/331
• CPC Class Codes: H01H 1/20 Bridging contacts for circuit breakers H01H73/045
• CPC Class Codes: H01H 1/66 Contacts sealed in an evacuated or gas-filled envelope, e.g. magnetic dry-reed contacts
• CPC Class Codes: H01H 71/526 the lever forming a toggle linkage with a second lever, the free end of which is directly and releasably engageable with a contact structure

Abstract

A breaker includes a contact unit provided in an airtight container. The contact unit has fixed contact points and a movable contact point which selectively contacts with the fixed contact points. Further, the breaker include a movable shaft having a part projecting outward from the airtight container, for moving the movable contact point to and from the fixed contact points, and a metal member for ensuring airtightness of the airtight container. The metal member has one end fixed to the airtight container and the other end fixed to the movable shaft and is extensible and contractible in accordance with the movement of the movable shaft. Moreover, the breaker includes a lever unit for moving the movable shaft between a closed position where the movable contact point is in contact with the fixed contact points and an open position where the movable contact point is separated from the fixed contact points.

Claims

1. A breaker comprising:

a contact unit provided in an airtight container, the contact unit having fixed contact points and a movable contact point which selectively contacts with the fixed contact points;

a movable shaft having a part projecting outward from the airtight container, for moving the movable contact point to and from the fixed contact points;

a metal member having one end fixed to the airtight container and the other end fixed to the movable shaft and being extensible and contractible in accordance with the movement of the movable shaft; and

a lever unit for moving the movable shaft between a closed position where the movable contact point is in contact with the fixed contact points and an open position where the movable contact point is separated from the fixed contact points.

2. The breaker of claim 1, wherein the lever unit is connected to the movable shaft.

3. The breaker of claim 1, further comprising a base for accommodating therein at least the contact unit, the movable shaft and the metal member,

wherein the lever unit includes:

an inner lever disposed in the base and connected to the movable shaft;

a manipulation portion projecting outward from the base; and

an outer lever having a pressing portion for pressing the inner lever in accordance with the manipulation of the manipulation portion, the pressing portion of the outer lever and the inner lever being not connected to each other, and

wherein when the inner lever moves from a position where the contact unit is in a closed state and passes beyond a predetermined position, a biasing unit biases the inner lever to a position where the contact unit reaches an open state, and a space where the inner lever moves is formed between the outer lever and the inner lever.

4. The breaker of claim 1, wherein the lever unit includes:

an inner lever connected to the movable shaft, the inner lever being disposed inside a base for accommodating therein at least the contact unit, the movable shaft and the metal member;

a manipulation portion projecting outward from the base; and

an outer lever having a pressing unit for pressing the inner lever in accordance with the manipulation of the manipulation portion,

the breaker further comprising;

a restricting unit which moves in accordance with a locking operation between a restriction position where the restricting unit is contacted with the pressing unit of the outer lever to restrict the movement of the outer lever and a release position where the restricting unit is separated from the outer lever to release the restriction of the movement of the outer lever;

a first biasing spring for applying elastic force for moving the restricting portion toward the restriction position;

a latch unit for maintaining the restricting unit in the release position; and

a second biasing spring for applying elastic force of a predetermined direction to the outer lever,

wherein a recess is formed at the outer lever so as to provide a gap between the outer lever and the restricting unit when the restricting unit is in the release position.

5. The breaker of claim 1, wherein the lever unit includes:

an inner lever connected to the movable shaft, the inner lever being disposed inside a base for accommodating therein at least the contact point portion, the movable shaft and the metal member;

a manipulation portion projecting outward from the base; and

an outer lever having a pressing portion for pressing the inner lever in accordance with the manipulation of the manipulation portion,

the breaker further comprising;

a restricting unit which moves in accordance with a locking operation between a restriction position where the restricting unit is contacted with the pressing unit of the outer lever to restrict the movement of the outer lever and a release position where the restricting unit is separated from the outer lever to release the restriction of the movement of the outer lever.

6. The breaker of claim 5, further comprising a latch unit for maintaining the restricting unit in the release position, wherein the lever unit has a releasing portion for releasing the latch of the latch unit.

7. The breaker of claim 1, further comprising a display unit for displaying the state of the contact unit in accordance with the manipulation of the lever unit.

8. The breaker of claim 3, further comprising a third biasing spring for pressing the outer lever to the inner lever.

9. The breaker of claim 1, further comprising an auxiliary contact unit whose contact points are opened and closed in accordance with the movement of the movable shaft.

10. The breaker of claim 1, wherein a predetermined gas having a pressure higher than about 1 atm is sealed in the airtight container.

11. The breaker of claim 10, wherein the gas contains at least one of hydrogen, nitrogen and carbon dioxide.

12. The breaker of claim 1, further comprising a restoring spring for restoring the movable shaft to the open position.

13. The breaker of claim 1, wherein the fixed contact points and the movable contact point are made of copper or copper alloy.

14. The breaker of claim 2, wherein the lever unit is formed as a single rod-shaped member having one end portion connected to the movable shaft and an intermediate portion serving as a fulcrum, and

wherein when the other end portion of the rod-shaped member is manipulated to rotate about the fulcrum, the movable shaft is moved between the closed position and the open position in accordance with the manipulation.

15. The breaker of claim 2, wherein the lever unit includes a first member having one end portion connected to the movable shaft, and a second member having one end portion connected to the other end portion of the first member and an intermediate portion serving as a fulcrum, and

wherein when the other end portion of the second member is manipulated to rotate about the fulcrum of the second member, the movable shaft is moved between the closed position and the open position in accordance with the manipulation.