Patents for H01F 21 - Variable inductances or transformers of the signal type (1,432)
06/1995
06/20/1995US5426409 Current controlled variable inductor
06/13/1995US5424691 Apparatus and method for electronically controlled admittance matching network
05/1995
05/24/1995EP0654802A1 Variable inductance element
05/04/1995DE4336483A1 Resonant electric circuit and method for tuning the resonant circuit
04/1995
04/19/1995EP0649152A2 Transformer integrable with a semiconductor integrated circuit and method for producing thereof
03/1995
03/15/1995EP0643404A2 Inductive structures for semiconductor integrated circuits
03/15/1995EP0643403A2 Inductive structures for semiconductor integrated circuits
03/15/1995EP0643402A2 Inductive structures for semiconductor integrated circuits
02/1995
02/21/1995US5392018 Electronically tuned matching networks using adjustable inductance elements and resonant tank circuits
01/1995
01/17/1995US5382937 Coil device
11/1994
11/22/1994US5367256 For sensing a rotational position of a shaft
10/1994
10/25/1994US5359315 Method of forming a three-layer structural spiral inductor
10/11/1994US5355275 Current limiting device for electromagnetic coil employing gap containing superconductive shield
09/1994
09/13/1994US5347255 Variable inductance coil device
09/06/1994US5345209 Adjustment system for a coil device
08/1994
08/23/1994US5341083 Contactless battery charging system
07/1994
07/13/1994CN2171905Y Multifunction welding repairing machine for vehicle
06/1994
06/15/1994EP0601919A1 Blocking device for windings of air core inductance
05/1994
05/18/1994EP0597497A1 Electronically tuned matching networks using adjustable inductance elements and resonant tank circuits
04/1994
04/28/1994WO1994009544A1 Contactless battery charging system
04/28/1994CA2147259A1 Contactless battery charging system
04/19/1994CA1328683C Deactivatable frequency-dividing-transponder tag
04/13/1994CN2161975Y Variometer
11/1993
11/24/1993EP0570666A1 Variable inductance coil device
10/1993
10/26/1993US5256999 Thread type magnetic core structure
09/1993
09/22/1993CN1076545A High stability multi-nominal value standard inducer
09/16/1993DE4206816A1 Balancing screw for inductive components - made as unit of ferrite body and plastic screw parts in recesses around body circumference.
03/1993
03/17/1993EP0532360A1 Transformer with controlled interwinding coupling and controlled leakage inductances and circuit using such transformer
12/1992
12/29/1992US5175526 Inductance device, particularly for short waves
10/1992
10/06/1992US5153547 High frequency coil
09/1992
09/01/1992US5144208 Device for adjusting a nominal value of the dimension of an actuator, the longitudinal dimension of which can be changed by applying an external electromagnetic or electrostatic field
07/1992
07/09/1992DE4143120A1 Tunable electric coil e.g. line resonator, filter - comprises resonant LC circuit with electronically variable inductor
07/01/1992EP0492884A1 Electromagnetic device
06/1992
06/03/1992CN1061677A Inductance device, particularly for short waves
05/1992
05/27/1992EP0487388A1 Inductor, particularly for short waves
05/24/1992CA2055658A1 Inductance device, particularly for short waves
03/1992
03/10/1992US5095357 Inductive structures for semiconductor integrated circuits
01/1992
01/09/1992DE4120097A1 HF coil assembly with thin walled core - having recess to prevent fracture by force applied by burr formed on cover during mfr.
01/09/1992DE4020305A1 Coil for surface mounting - has former that responds to heating to adjust shape and vary inductance
11/1991
11/06/1991CN1014660B Amplitude coil for final cascade of line scanning of television set
10/1991
10/29/1991US5061896 Variable transformer to detect linear displacement with constant output amplitude
10/15/1991US5057809 Variable inductance RF coil assembly
09/1991
09/24/1991US5051710 Variable Zo transmission line transformer
08/1991
08/28/1991EP0443173A1 Wideband tunable monolithic inductor
07/1991
07/17/1991CN2081173U Automatic electronic contactless switch for single-phase motor
06/1991
06/29/1991CA2028201A1 Automated adjustment of air-core coil inductance
06/27/1991DE3942509A1 HF circuit with tunable printed coil - having inductance varied by moving relative position of ferrite element i.e. by distance or amt. of coverage
06/04/1991US5021758 Circuit arrangement comprising MESFET switched spiral inductor
04/1991
04/17/1991EP0422609A1 Linearizing coil for linearizing the line current of image layer devices
03/1991
03/27/1991EP0215840B1 Inductance coil sensor
03/07/1991DE3929514A1 Miniature inductive component for HF and VHF range - has axis of wound wire vertical to base support of plastics material to allow surface mounting
02/1991
02/20/1991EP0413348A2 Semiconductor integrated circuit
02/14/1991DE3926231A1 Small, tunable inductance for HF circuitry - has parallel wound turns of two coils with identical dia.
01/1991
01/22/1991US4987390 Superconducting reversible variable inductor
01/02/1991EP0405764A1 Conversion of bias strip in a frequency-dividing transponder tag into a tripole bar magnet to deactivate the tag
12/1990
12/31/1990CA2018267A1 Conversion of bias strip in a frequency-dividing-transponder tag into a tripole bar magnet to deactivate the tag
12/25/1990US4980663 Automated adjustment of air-core coil inductance
11/1990
11/06/1990US4968972 Conversion of bias strip in a frequency-dividing-transponder tag into a tripole bar magnet to deactivate the tag
08/1990
08/14/1990CA1272777A1 Inductance coil sensor
06/1990
06/20/1990CN1008490B Coil with magnetisable rod core
04/1990
04/17/1990US4917317 Toroidal coil winding machine
02/1990
02/08/1990DE3826431A1 Method for narrow-tolerance inductance trimming of an electrical component which is provided with connecting pins or has no connecting pins, can be surface mounted, is inductive and has no trimming elements
01/1990
01/31/1990EP0352936A2 Deactivatable frequency-dividing-transponder tag
11/1989
11/23/1989DE3816868A1 Adjustable linearity coil for video display units
11/21/1989US4882569 Deactivatable fequency-dividing-transponder tag
03/1989
03/30/1989DE3730303A1 Tunable helical circuit
03/30/1989DE3730302A1 Tunable helical band-pass filter for the radio-frequency region
03/29/1989EP0309359A1 Method for automatically controlling the self-inductance of wound elements comprising a magnetic circuit with an adjustable air gap
02/1989
02/21/1989US4806831 Coil with magnetizable rod core
02/14/1989CA1250018A1 Controlled inductive coupling device
11/1988
11/17/1988EP0290928A1 Radiofrequency tuning inductor
10/1988
10/27/1988DE3711529A1 Circuit component module for video recorder or cordless telephone - uses terminal lead frame for securing components before embedding in resin block
10/11/1988US4777436 Inductance coil sensor
09/1988
09/27/1988US4774490 Rotary Electric devices
09/13/1988US4771200 Synchro generator asymmetric magnetically conductive rotor
08/1988
08/23/1988CA1241064A1 Phase lag adjustment in electric meter
08/16/1988US4764744 Overload relay having adjustably gapped current transformers
06/1988
06/29/1988CN87212290U No-load capacitance-regulating transformer
06/29/1988CN87205770U Multi-tap adjustable fluorescent-lamp ballast
06/15/1988CN85205184U 多功能控制器 Multi-function controller
02/1988
02/16/1988US4725805 Electric current control type variable inductor
12/1987
12/16/1987CN87104021A Amplitude coil for final cascade of line scanning of television set
12/09/1987EP0248329A2 Amplitude coil for the output line deflection stage of a television receiver
12/03/1987DE3618122A1 Tunable filter coil
12/02/1987EP0247997A1 Rotary transmitter
08/1987
08/11/1987US4685395 Controlled inductive coupling device
07/1987
07/14/1987US4680566 Coil with magnetisable rod core
06/1987
06/29/1987EP0215840A4 Inductance coil sensor.
06/24/1987CN86100524A Contactual voltage-regulating autotransformer with multilayer winding
05/1987
05/07/1987DE3539135A1 Air-cored coil which can be trimmed
04/1987
04/14/1987US4657719 Forming thin film of resin an hardening
04/07/1987US4656452 Transformer telephone influence tractor core shunt
04/01/1987EP0215840A1 Inductance coil sensor.
03/1987
03/10/1987US4649459 Rotary electric devices
03/10/1987US4649337 Phase lag adjustment in electric meter
02/1987
02/12/1987DE3527442A1 Method and device for modifying the quality factor of a coil
01/1987
01/22/1987DE3525649A1 Coil having a pin core which can be magnetized
01/14/1987CN85106925A Coil with magnetisable rod core
01/06/1987US4634126 Device for converting the amount of a mechanical displacement into electrical signal
12/1986
12/23/1986US4631510 Harmonically graded airgap reluctance-type rotating electric resolver
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