EP0059770B1
Expired / Lapsed
EP
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Device for recording a magnetic field
Assignee: Rockwell Collins Deutschland GmbH
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Filing: 1981-03-07
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Granted: 1985-11-21
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Expires: 2001-03-07
Abstract
No abstract record available.
Inventors
- 👤 Heinz Dr. Rer. Nat. Wehde
- 👤 Hermann Kiesewetter
- 👤 Hermann Dipl.-Ing. Klotz
- 👤 Joachim Dr. Ing. Rogge
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 08:43
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
189 words
An instrument for detecting a magnetic field, containing a thin, substantially annular core (24) of magnetic material which is surrounded by an exciter coil (30) and by - preferably four - pick-up coils (31 to 34) which are disposed axially symmetrically, an evaluation circuit for the signal voltages of the pick-up coils (31 to 34) and an annular coil former (20) which comprises an annular groove (23) in one face to receive the core (24), characterised in that slots (27, 28), which extend at least partially round the coil former (20) and the planes of symmetry of which lie in planes which are turned through specific divisions and which also contain the longitudinal axis of the coil former, which slots are penetrated perpendicularly by the annular groove (23) receiving the core (24), are provided to receive the exciter coil (30) and the pick-up coils (31 to 34), and that connected to the coil former (20) is a cover (21), the annular extension (25) of which projects into the annular groove (23) to locate the core (24), the core (24) being constructed in the form of a single annular disc.
Claim 2
Dependent Claim
189 words
An instrument for detecting a magnetic field, containing a thin, substantially annular core (24) of magnetic material which is surrounded by an exciter coil (30) and by - preferably four - pick-up coils (31 to 34) which are disposed axially symmetrically, an evaluation circuit for the signal voltages of the pick-up coils (31 to 34) and an annular coil former (20) which comprises an annular groove (23) in one face to receive the core (24), characterised in that slots (27, 28), which extend at least partially round the coil former (20) and the planes of symmetry of which lie in planes which are turned through specific divisions and which also contain the longitudinal axis of the coil former, which slots are penetrated perpendicularly by the annular groove (23) receiving the core (24), are provided to receive the exciter coil (30) and the pick-up coils (31 to 34), and that connected to the coil former (20) is a cover (21), the annular extension (25) of which projects into the annular groove (23) to locate the core (24), the core (24) being constructed in the form of a single annular disc.
Claim 3
Dependent Claim
67 words
An instrument as claimed in Claim 1, characterised in that the slots (27, 28) are disposed over the circumference of the coil former (20), in the four quadrants, axially symmetrically in each case, and that one of the pick-up coils (31 to 34) is disposed in each quadrant in the same manner so that their major axes are each offset by 90° in relation to one another.
Claim 4
Dependent Claim
104 words
An instrument as claimed in Claim 1 or 2, characterised in that the coil former (20) comprises two yokes (17, 18) which are situated diametrically opposite one another and directed upwards for the Cardanic suspension and that a Cardan ring (10) is provided, the first shafts (13, 14) of which engage in bushes (15, 16) in the said yokes, and of which the second shafts (11, 12), which are disposed offset by 90° at its circumference in relation to the first shafts, engage in bushes (7, 8) in the cover (2) which closes the housing (1) receiving the coil former (20) at the top.
Claim 5
Dependent Claim
37 words
An instrument as claimed in Claim 3, characterised in that the diameter of the said bushes (7, 8, 15, 16) are each larger, by about 20 %, than the diameters of the shafts (11, 12, 13, 14).
Claim 6
Dependent Claim
37 words
An instrument as claimed in one of the preceding Claims, characterised in that a pendulum weight (22) having substantially the shape of a part of a sphere, is disposed at the underside of the coil former (20).
Claim 7
Dependent Claim
51 words
An instrument as claimed in one of the preceding Claims, characterised in that two windings of a Helmholz coil (29), through which a direct current flows to compensate for the vertical component of a permanent magnetic field, are provided at the outside of the housing (1) receiving the coil former (20).
Claim 8
Dependent Claim
94 words
An instrument as claimed in one of the Claims 1 to 6, characterised in that the evaluation circuit to evaluate the signal voltages (S 1 , S z ) appearing in the diametrally oposite pick-up coils (31, 32 or 33, 34) contains a phase sensitive rectifier (44) to which the signal voltages (S l , S 2 ) are supplied alternately through the analogue switches (40, 41), and that the phase-sensitive rectifier (44) is preceded by a filter (42) which only passes the second harmonic (U, or U z ) of the exciter frequency.
Claim 9
Dependent Claim
65 words
An instrument as claimed in Claim 7, characterised in that an oscillator 37 is provided from the frequency-stable pulse train of which there are derived - preferably through dividers (38, 39) - both a frequency (SF) for a driving circuit (36) whereby the exciter coil (30) is driven, and control signals (UM, DEMO, AZ) for the analogue switch (40, 41) and the phase-sensitive rectifier (44).
Claim 10
Dependent Claim
73 words
An instrument as claimed in one of the Claims 7 or 8, characterised in that the phase- sensitivie rectifier (44) is followed, via an analogue-digital converter (60), by a computer (66) with which the direction of the magnetic field acting on the pick-up coils (31, 34) can be determined from the signal voltages (S 1' S 2 ) according to the amplitude and phase position of the second harmonic (U i or Uo.
Claim 11
Dependent Claim
146 words
An instrument as claimed in Claim 9, characterised in that, after each switching over of an analogue switch (40 or 41), a further analogue switch (51) is actuated by the control signal (AZ) and a reference quantity for the second harmonic (U i or U 2 ), formed from a zero adjustment, is fed into the computer (66) and stored, and that, taking into consideration the transient time of the filter (42), another further analogue switch (50) is actuated by the control signal (AZ) for the input of the filtered and analogue-digital converted second harmonic (U i or U 2 ) into the computer, and the computer forms, from the signal now reaching it and the stored reference quantity, a difference signal which corresponds in sign to the phase position and in amount to the amplitude of the second harmonic (U 1 or U 2 ).
References Cited (Backward Citations)
No citation records indexed.
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