EP0122777A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Intrinsically safe signal coupler
Assignee: Gilbarco Inc
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Filing: 1984-04-12
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Granted: —
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Expires: 2004-04-12
Abstract
Abstract Energy limiting, bidirectional signal passage, bandpass filtering, and DC isolation is provided via apparatus including a ferrite core transformer (29) potted within a cavity (33) of an explosion proof housing (9) mounted upon a wall of a tank (1), whereby one winding (45) ofthetransformer(29) is connected to outside equipment (21), and another winding (51) of the transformer (29) is connected to equipment (3) located within the tank (1).
Inventors
- 👤 James Oliver Steger
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:35
CPC Classifications
H; H02; H02H; H02H9/00; H02H9/008
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
132 words
An intrinsically safe apparatus for coupling electrical signals between a safe first zone (19), and a relatively unsafe second zone (1) containing highly combustible matter, characterised in that it comprises : signal coupling means (29) for both bidirectionally passing desired electrical signals with substantially no attenuation, between said first and second zones, and for substantially limiting to a safe level the energy content of any electrical signals passed into said second zone; and housing means (9) including mechanical barrier means (31), for enclosing said signal coupling means (29) within said mechanical barrier means (31) between said first and second zones (19, 1) for physically isolating said first zone (19) from said second zone (1), the combination of said housing means (9) and said signal coupling means (29) making said apparatus intrinsically safe.
Claim 2
Dependent Claim
132 words
An intrinsically safe apparatus for coupling electrical signals between a safe first zone (19), and a relatively unsafe second zone (1) containing highly combustible matter, characterised in that it comprises : signal coupling means (29) for both bidirectionally passing desired electrical signals with substantially no attenuation, between said first and second zones, and for substantially limiting to a safe level the energy content of any electrical signals passed into said second zone; and housing means (9) including mechanical barrier means (31), for enclosing said signal coupling means (29) within said mechanical barrier means (31) between said first and second zones (19, 1) for physically isolating said first zone (19) from said second zone (1), the combination of said housing means (9) and said signal coupling means (29) making said apparatus intrinsically safe.
Claim 3
Dependent Claim
34 words
Apparatus according to claim I, wherein said signal coupling means (29) and said mechanical barrier means (31) are such that, together, they provide DC electrical isolation between said first and second zones (19, 1).
Claim 4
Dependent Claim
55 words
Apparatus according to claim 1 or 2, wherein said signal coupling means includes : transformer means (29) including a primary winding (45) adapted for receiving and delivering electrical signals in association with said first zone (19), and a secondary winding (51) adapted for receiving and delivering electrical signals in association with said second zone (1).
Claim 5
Dependent Claim
15 words
Apparatus according to claim 3, wherein said transformer means includes a toroid core transformer (29).
Claim 6
Dependent Claim
48 words
Apparatus according to claim 4, wherein said toroid core transformer includes both a toroid core (65) having a substantially high internal resistivity, and said primary and secondary windings (45, 51) having no direct electrical connection therebetween, for providing electrical isolation between said first and second zones (19, 1).
Claim 7
Dependent Claim
14 words
Apparatus according to claim 5, wherein said toroid core (65) consists of ferrite material.
Claim 8
Dependent Claim
23 words
Apparatus according to any one of claims 3 to 6, wherein said primary and secondary windings (45, 51) have a 1-to-1 turns ratio.
Claim 9
Dependent Claim
47 words
Apparatus according to any one of claims 3 to 7, wherein said mechanical barrier means of said housing means (9) includes : a barrier head (35) having a first interior cavity (33) for containing said toroid core transformer (29); and potting material (31) filling said cavity (33).
Claim 10
Dependent Claim
62 words
Apparatus according to claim 8, wherein said housing means (9) further includes : said barrier head (35) having a second interior cavity (37) connected to said first interior cavity (33); and first electrical connecting means (47, 49) within said second cavity (37) for providing electrical connecting access from said first zone (19) to the primary winding (45) of said toroid transformer (29).
Claim 11
Dependent Claim
78 words
Apparatus according to claim 8 or 9, wherein said housing means (35, 55) further includes : standpipe head means (55) for connection to a lowermost portion of said barrier head (35), said standpipe head means (55) including a cavity (60) therein; and second electrical connecting means (53, 63) within the cavity (60) of said standpipe head means (55) for providing electrical connecting access from said second zone (1) to the secondary winding (51) of said toroid transformer (29).
References Cited (Backward Citations)
No citation records indexed.
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