EP0011972A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electrical switchgear
Assignee: Hawker Siddeley Switchgear Ltd
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Filing: 1979-11-19
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Granted: —
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Expires: 1999-11-19
Abstract
Abstract On opening of a circuit breaker, an end portion 19 of a pivotable contact arm 12 disengages from fixed contacts 7 such that an arc is drawn therebetween radially across the pole face of a field coil 9, the end portion 19 moving transversely to the field coil axis. The arc then transfers from the contacts 7 to a tubular electrode 24 thereby bringing the field coil 9 into circuit so that a magnetic field is generated which causes the arc to rotate and become extinguished. In the fully-open position of the circuit breaker, the end portion 19 lies along the field coil axis. The whole assembly is disposed in a housing 2 which contains the highly insulating gas sulphur hexafluoride. A single field coil and electrode can be shared between two such constructions. Arrangements are also disclosed (Figures 11 to 14) in which the initial arc is drawn directly between the contact arm 12 and the electrode 24.
Inventors
- 👤 John Parry
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 10:03
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/02; H01H33/04; H01H33/18; H01H33/187
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
104 words
Electrical switchgear employing an electrically insulating fluid for arc extinction in which during disengagement of first and second contacts an arc is drawn radially across the pole face of a field coil between the first contact and an arcing electrode, the arcing current flowing through the field coil to produce a magnetic field which causes the arc to rotate and become extinguished, characterised in that the first contact (12) is pivotable about an axis transverse to the axis of the field coil (9) and has an end portion (19) which moves transversely and inwardly of the field coil axis when the conta.cts are opened.
Claim 2
Dependent Claim
104 words
Electrical switchgear employing an electrically insulating fluid for arc extinction in which during disengagement of first and second contacts an arc is drawn radially across the pole face of a field coil between the first contact and an arcing electrode, the arcing current flowing through the field coil to produce a magnetic field which causes the arc to rotate and become extinguished, characterised in that the first contact (12) is pivotable about an axis transverse to the axis of the field coil (9) and has an end portion (19) which moves transversely and inwardly of the field coil axis when the conta.cts are opened.
Claim 3
Dependent Claim
27 words
Electrical switchgear according to claim 1, wherein the contact end portion (19) is elongate and lies along the field coil axis when the switchgear is fully open.
Claim 4
Dependent Claim
26 words
Electrical switchgear according to claim 1 or 2, wherein the contact end portion (319) extends into the field coil (309) when the switchgear is fully open.
Claim 5
Dependent Claim
26 words
Electrical switchgear according to claim 1, 2 or 3 wherein the first contact (312) is pivoted at a point (313) spaced from the field coil axis.
Claim 6
Dependent Claim
29 words
Electrical switchgear according to any preceding claim, wherein the first contact (312) is a cranked arm which is pivoted at an end thereof remote from said end portion (319).
Claim 7
Dependent Claim
34 words
Electrical switchgear according to any preceding claim, further comprising a preferably annular ferromagnetic member (451) is disposed at least partly within the field coil (409) to concentrate the magnetic field produced by the latter.
Claim 8
Dependent Claim
21 words
Electrical switchgear according to claim 6, wherein the arcing electrode (424) is tubular and has the ferromagnetic member (451) disposed therein.
Claim 9
Dependent Claim
55 words
Electrical switchgear according to any preceding claim wherein the field coil (9) is connected to the second contact (7) such that during opening of the switchgear an arc is first drawn between the first contact (12) and the second contact (7), and is then transferred from the second contact (7) to the arcing electrode (24).
Claim 10
Dependent Claim
31 words
Electrical switchgear according to claim 9, wherein a ferromagnetic yoke (452) is associated with the second contact (407) to assist in positioning the initial arc on the contact end portion (419).
Claim 11
Dependent Claim
33 words
Electrical switchgear according to any one of claims 1 to 7 wherein the first contact (612) engages the arcing electrode (624) before disengaging from the second contact (607) during opening of the switchgear.
Claim 12
Dependent Claim
47 words
Electrical switchgear according to any preceding claim wherein the field coil (9) is composed of a. self-supporting strip of conducting material arranged in a spiral, an outer end of the spiral being attached to mounting means (8) and an inner end thereof mounting the arcing electrode (24).
Claim 13
Dependent Claim
33 words
Electrical switchgear according to any preceding claim, wherein the arcing electrode (24) is in the form of a tubular member about the outside of which the turns of the field coil (9) run.
Claim 14
Dependent Claim
20 words
Electrical switchgear according to claim 12, wherein the tubular member ha.s a flange (340) which faces the first contact (312).
Claim 15
Dependent Claim
25 words
. Electrical switchgear according to claim 12 or 13, wherein the tubular member has an internal annular projection (341) along which the rotating arc runs.
Claim 16
Dependent Claim
42 words
Electrical switchgear according to any preceding claim, including two switches (201a, 201b) each of which has respective first and second contacts (212, 207), the switches sharing a common field coil (209) on opposite sides of which the first contacts are respectively disposed.
Claim 17
Dependent Claim
21 words
Electrical switchgear according to claim 15, wherein the arcing electrode (224) is a tubular member common to both switches (201a, 201b).
Claim 18
Dependent Claim
21 words
Electrical switchgear according to claim 15 or 16, wherein an insulating member (231) is arranged transversely within the arcing electrode (224).
Claim 19
Dependent Claim
36 words
Electrical switchgear according to any preceding claim, including a plurality of switches (201a, 201b, 201c) each having respective first and second contacts (212, 207), the second contacts (207) being mounted on a common insulating support (232).
Claim 20
Dependent Claim
31 words
Electrical switchgear according to claim 18, including three switches (201a, 201b, 201c) and two field coils (209), one of the field coils being shared between two of the switches (201a, 201b).
Claim 21
Dependent Claim
25 words
Electrical switchgear according to claim 18, including four switches and two field coils, each field coil being common to a respective pair of the switches.
Claim 22
Dependent Claim
53 words
Electrical switchgear according to any one of claims 1 to 15, including a plurality of switches (101a, 101b, 101c) each having a respective field coil (109) and a respective arcing electrode (124), the switches being disposed substantially on a common axis (127) with the field coils (109) mutually staggered transversely of said axis.
Claim 23
Dependent Claim
23 words
Electrical switchgear according to claim 21, including three switches (101a, lOlb, 101c) whose a.ssociated field coils (109) are disposed in a triangular array.
Claim 24
Dependent Claim
20 words
Electrical switchgear according to any preceding claim wherein the electrically insulating fluid is a. highly insulating ga.s, preferably sulphur hexafluoride.
References Cited (Backward Citations)
No citation records indexed.
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