Device for adjusting the inductance of a coil
AssigneeU.S. Philips Corporation
InventorsRaymond Salvy, Guy Brugerie
Life of this patent
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Abstract
A device for automatic adjustment of the inductance of a coil by utilizing a magnetic core which is formed by means of a magnetic paste. The device defines the quantity of magnetic paste in dependence on an inductance value measured by means of an inductance measuring apparatus.
Claims8
A device for adjusting the inductance of a coil having a core which includes a mixture of a soft magnetic material and a binder material, said device comprising, a control circuit, a comparison circuit having two inputs and an output, a nozzle for injecting a magnetic paste, said nozzle comprising an electric valve with a control winding coupled via the control circuit to the output of the comparision circuit, means connecting a first input of the comparison circuit to the output of an inductance measuring apparatus which is connected to the connections of the coil to be adjusted, and means connecting the second input of the comparison circuit to a reference voltage source.
A device for adjusting the inductance of a coil having a magnetic core comprising, means for injecting a magnetic material into the core of said coil, said injecting means having a control input for controlling the flow of said magnetic material, a comparison circuit having first and second inputs and an output, a source of reference voltage that determines the inductance value of said coil, an inductance measuring device having an input connected to said coil and an output connected to the first input of the comparison circuit, a control circuit, means coupling the output of the reference voltage source to the second input of the comparison circuit, and means coupling the output of the comparison circuit to the control input of the injecting means via said control circuit thereby to control the flow of magnetic material to the core of the coil as a function of the measured inductance of the coil.
Dependencies are inferred from the claim text.