Claims
- 1. A current limiting device comprising:first and second contact members, each contact member having a first end with a contact, the contacts of said first and second contact members defining a contact pair; means for applying a contacting pressure to said contact pair; a tubular insulator adjacent to and circumferentially surrounding said contact pair in a closed state of said contact pair, at least one of said first and second contact members being rotatably supported at a second end; and an electrical path including said first and second contact members and through which current flows, said electrical path including first and second parts directly opposite each other so that the current flows in opposite directions through said first and second parts, wherein said first ends are positioned within a cylindrical space defined by said tubular insulator when said contact pair is in the closed state, and said contact of said rotatably supported contact member is positioned outside of the cylindrical space when said contact pair is in an open state so that, upon initial opening of said contact pair in response to an excessive current flow through said first and second parts, and formation of an arc between said first and second contact members, gas pressure at the arc is increased due to gas confinement within said tubular insulator.
- 2. The current limiting device as claimed in claim 1 comprising:a movable member having a movable contact and a movable arm rotatable about a movable member rotary shaft; a stationary member having a stationary contact making said contact pair with said movable contact, and a stationary conductor opposing said movable arm, said stationary conductor and said movable arm comprising said first and second parts of said electrical path; a contact pressure spring as said means for applying the contacting pressure to said contact pair, said movable arm having a first movable arm portion and a second movable arm portion, substantially defining an L-shape, and, in the closed state, said first movable arm portion is positioned to provide an electrical current flow substantially parallel to and opposite in direction from said stationary conductor; and a movable member tip portion having said movable contact and a stationary member tip portion having said stationary contact positioned within the cylindrical space, wherein, in the open state, said movable contact is positioned outside of the cylindrical space.
- 3. The current limiting device as claimed in claim 2, including a conductor bent substantially into a U-shape with a first end connected to a terminal portion of said movable member remote from said movable member rotary shaft, and a second end having on an inner side said stationary contact, said stationary member on which said stationary contact is disposed being substantially opposite said first movable arm portion in the closed state, said stationary member including a slit for opening and closing of said movable member at a position crossing a rotary trace of said movable member, a portion, other than said stationary contact, of said stationary member directly facing said movable contact in the open state being covered by an insulating material.
- 4. The current limiting device as claimed in claim 2, wherein said stationary member is a conductor connected to a terminal portion of said movable member remote from said movable member rotary shaft and includes a stationary conductor having said stationary contact making said contact pair with said movable contact and opposing said first movable arm portion of said movable member and through which an electrical current flows opposite in direction to current flow through said movable arm, and including a magnetic core on the electrical path disposed at opposite sides of said stationary conductor and introducing a current to said stationary conductor from said terminal portion.
- 5. The current limiting device as claimed in claim 1, comprising:a movable member having a movable contact and a movable arm and rotatable about a movable member rotary shaft; a repulsing member having a repulsing contact making said contact pair with said movable contact and a repulsing arm substantially opposing said movable arm and rotatable about a repulsive member rotary shaft; a contact pressure spring as said means for applying the contacting pressure to said contact pair, a pressure accumulating space communicating at a main opening with the cylindrical space defined by said tubular insulator and containing said repulsing member, said repulsing arm having a first repulsing arm portion and a second repulsing arm portion substantially defining an L-shape and, in the closed state, said first repulsing arm portion is positioned to provide a current flow substantially parallel to and opposite in direction with respect to a portion of said movable arm, and a movable member tip portion having said movable contact, and a repulsing member tip portion having said repulsing contact positioned within the cylindrical space defined by said tubular insulator, and, in the open state, said movable contact member tip portion is positioned outside of the cylindrical space.
- 6. The current limiting device as claimed in claim 5, wherein the electrical path for supplying a current to said repulsing member intersects a plane including a contact opening locus of said repulsing member, the electrical path including a slot for opening and closing of one of said repulsing member and said movable member, and the electrical path is closer to said movable arm than to said first repulsing arm portion so that an electrical current flows parallel to and opposite to said first repulsing arm portion.
- 7. The current limiting device as claimed in claim 1, comprising:a movable member contained within an electrically insulating housing and having a movable contact and a substantially L-shaped movable arm rotatable about a movable member rotary shaft; a stationary member having a stationary contact making said contact pair with said movable contact and the electrical path is substantially parallel to one portion of said movable arm for electrical current flow in a direction opposite said movable arm upon contact closing; an arc extinguishing plate opposing a tip of said movable member; and terminals disposed on a side of said insulating housing opposite from said movable contact and connected to said movable member and said stationary member, respectively, said stationary member being substantially perpendicular to a line connecting said terminals.
- 8. The current limiting device as claimed in claim 2, wherein said tubular insulator has a wall that is higher opposite said movable member rotary shaft than adjacent said movable member rotary shaft.
- 9. The current limiting device as claimed in claim 2, including a housing housing said movable member, said stationary member, and said tubular insulator, said housing having an exhaust port in a face of said housing, opposite said movable member rotary shaft as viewed from said movable contact, and wherein said exhaust port has an area no larger than one half the face of said housing including said exhaust port and positioned proximate said movable member in the open state.
- 10. The current limiting device as claimed in claim 2, wherein the portion of said stationary conductor opposing said movable member and through which an electrical current flows opposite to the electrical current flowing in said movable member is bent toward said movable member.
- 11. A circuit interrupter having a current limiting function comprising:a movable member having a movable contact and a movable arm and rotatable about a movable member rotary shaft; a stationary member having a stationary contact making a contact pair with said movable contact and a stationary conductor substantially opposing said movable arm; a tubular insulator adjacent to and circumferentially surrounding said contact pair in a closed state; and a contact pressure spring providing contacting pressure to said contact pair, said contact pair being positioned within a cylindrical space defined by said tubular insulator in the closed state, and said movable contact being positioned outside of the cylindrical space in an open state so that, upon initial opening of said contact pair in response to an excessive current flow through said movable arm and said stationary conductor, and formation of an arc between said movable contact and said stationary contact, gas pressure at the arc is increased due to gas confinement within said tubular insulator.
- 12. The circuit interrupter having a current limiting function as claimed in claim 11, wherein said movable arm has a first movable arm portion and a second movable arm portion defining an L-shape, and, in the closed state, said first movable arm portion is positioned to provide a current flow parallel to and opposite in direction from current flow in said stationary conductor.
- 13. The circuit interrupter having a current limiting function as claimed in claim 11, wherein said tubular insulator has a wall that is higher opposite said movable member rotary shaft than adjacent said movable member rotary shaft.
- 14. The circuit interrupter having a current limiting function as claimed in claim 11, wherein said stationary conductor and one portion of a conductor for supplying an electrical current to said movable member are parallel and located, relative to each other, so that electrical currents flowing through both of said stationary conductor and said conductor supplying current to said movable member coincide in direction of current flow.
- 15. The circuit interrupter having a current limiting function as claimed in claim 11, including a housing housing said movable member, said stationary member, and said tubular insulator, the housing having an exhaust port in a face of the housing opposite said movable member rotary shaft as viewed from said movable contact, and wherein said exhaust port has an area no larger than one half the face of the housing including the exhaust port and positioned proximate said movable member in the open state.
- 16. The circuit interrupter having a current limiting function as claimed in claim 11, wherein said stationary contact is positioned within a pressure accumulating space in communication with the cylindrical space.
- 17. The circuit interrupter having a current limiting function as claimed in claim 11, further comprising an arc extinguisher plate disposed at a position opposing a tip of said movable member and an arc runner extending along a current carrying conductor to said stationary member, an end portion of said arc runner being exposed to a side of the arc extinguisher plate opposite a center of said movable member rotary shaft.
- 18. The circuit interrupter having a current limiting function as claimed in claim 11, wherein said stationary conductor having said stationary contact is bent into substantially a U-shape to lead to a far side from said movable member rotary shaft, and including a slit, for closing of said movable member, in a portion of said stationary conductor intersecting with a rotation locus of said movable member.
- 19. A current limiting device comprising:a movable member contained within an electrically insulating housing and having a movable contact and an L-shaped movable arm rotatable about a movable member rotary shaft; a stationary member having a stationary contact making a contact pair with said movable contact and an electrical path substantially parallel to one portion of said movable arm for flow of an electrical current in a direction opposite current flow in said movable arm upon contact closing; a tubular insulator adjacent to and circumferentially surrounding the contact pair in a closed state; biasing means for applying contacting pressure to said contact pair; an arc extinguishing plate opposing a tip of said movable member; and terminals disposed on a side of said insulating housing opposite said movable contact and said stationary member, said contact pair, in the closed state, being positioned within a cylindrical space defined by said tubular insulator and, in an open state, said movable contact being positioned outside of the cylindrical space so that, upon initial opening of said contact pair in response to an excessive current flow through said movable member and said stationary member, and formation of an arc between said movable contact and said stationary contact, gas pressure at the arc is increased due to gas confinement within said tubular insulator.
- 20. The current limiting device as claimed in claim 19, including an arc runner extending along a current carrying conductor to said stationary member, a tip portion of said arc runner being exposed to a side of said arc extinguisher plate.
Priority Claims (4)
Number |
Date |
Country |
Kind |
10-372462 |
Dec 1998 |
JP |
|
11-010745 |
Jan 1999 |
JP |
|
11-069986 |
Mar 1999 |
JP |
|
11-240066 |
Aug 1999 |
JP |
|
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation of International Application PCT/JP99/07303, with an international filing date of Dec. 24, 1999, and designating the United States the contents of which are hereby incorporated by reference.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4644307 |
Tanimoto |
Feb 1987 |
A |
Foreign Referenced Citations (4)
Number |
Date |
Country |
1-43973 |
Sep 1989 |
JP |
8-8048 |
Jan 1996 |
JP |
8-250006 |
Sep 1996 |
JP |
10-269923 |
Oct 1998 |
JP |
Continuations (1)
|
Number |
Date |
Country |
Parent |
PCT/JP99/07303 |
Dec 1999 |
US |
Child |
09/641268 |
|
US |