Monitoring of magnetically permeable particles in a carrier material

Claim 3

A method according to claim 1, characterized in producing the signal by measuring the resonant frequency of the circuit.

Claim 4

A method according to claim 1, wherein the composite material is fluid and the method is characterized in holding the composite material in a dielectric vessel surrounded by the inductor coil.

Claim 5

A method according to claim 3, characterized in passing the material continuously along the vessel provided with an inlet and outlet and producing signals continuously which correspond to the inductance of the coil.

Claim 6

A method according to claim 1, wherein the composite material is a dry dielectric layer provided upon a conductor and the method is characterized in passing the layer covered conductor along a fixed pass line through the coil and producing signals corresponding to the inductance of the coil as the conductor is passed through the coil, the inductance influenced by the quantity of particles within the coil and progressively along the conductor.

Claim 9

A method according to claim 6, characterized in passing the composite material in fluid form through a vessel disposed radially within the inductor coil and having an inlet and an outlet, producing signals continuously, each signal corresponding to the inductance of the coil as the material passes through the vessel, and operating the control means dependent upon the evaluation of each signal.

Claim 10

A method according to claim 6, wherein the composite material is a dry dielectric layer provided upon a conductor, the method characterized in passing the layer covered conductor along a fixed pass line through the coil and producing signals continuously, each signal corresponding to the inductance of the coil as the conductor is passed through the coil, and operating the control means dependent upon the evaluation of each signal.

Claim 11

Apparatus for monitoring the quantity of magnetically permeable particles dispersed within a carrier in a composite material characterized in comprising an inductor coil (28), a retaining means (30, 58) to house the composite material in a fixed radial position within the coil, and means (32) for providing an electrical signal corresponding to the inductance of the coil.

Claim 12

Apparatus for monitoring the quantity of magnetically permeable particles dispersed within a carrier in a composite material characterized in comprising an inductor coil (28), a retaining means (30, 58) to house the composite material in a fixed radial position within the coil, and means (32) for providing an electrical signal corresponding to the inductance of the coil.

Claim 13

Apparatus according to claim 9, characterized in that the means for providing the signal comprises an oscillator (32) which operates at the resonant frequency of the coil.

Claim 14

Apparatus according to claim 9, characterized in that the retaining means comprises a dielectric vessel (30, 58) disposed within the inductor coil.

Claim 15

Apparatus according to claim 9, characterized in that the retaining means comprises a guide (58) to hold a conductor along a fixed pass line through the coil, the conductor having a dry covering layer formed from the composite material.

Claim 16

Apparatus for controlling the quantity of magnetically permeable particles dispersed within a carrier in a composite material during continuous preparation and removal of the composite material in fluid form, the apparatus characterized in comprising a mixing device (10, 18); valve means (54, 56) to control the addition of separate ingredients into the mixing device (18); an inductor coil (28) disposed downstream from the mixing device (10, 18) along a pass line for- the compose material; a retaining means (30, 58) to hold the composite material in a fixed radial position within the coil; means (32) for providing an electrical signal corresponding to the inductance of the coil, said means comprising a first oscillator (32) which operates at the resonant frequency of the coil circuit; a second oscillator (40) to provide a signal corresponding to a datum oscillation; evaluating means (50) for the signals; and control means (52) operable upon an evaluation differing from that representing a desired quantity of particles, to adjust the valve means and affect the relative rates of input of the ingredients thereby to adjust the quantity of particles towards that desired.

Claim 17

Apparatus for controlling the quantity of magnetically permeable particles dispersed within a carrier in a composite material during continuous preparation and removal of the composite material in fluid form, the apparatus characterized in comprising a mixing device (10, 18); valve means (54, 56) to control the addition of separate ingredients into the mixing device (18); an inductor coil (28) disposed downstream from the mixing device (10, 18) along a pass line for- the compose material; a retaining means (30, 58) to hold the composite material in a fixed radial position within the coil; means (32) for providing an electrical signal corresponding to the inductance of the coil, said means comprising a first oscillator (32) which operates at the resonant frequency of the coil circuit; a second oscillator (40) to provide a signal corresponding to a datum oscillation; evaluating means (50) for the signals; and control means (52) operable upon an evaluation differing from that representing a desired quantity of particles, to adjust the valve means and affect the relative rates of input of the ingredients thereby to adjust the quantity of particles towards that desired.

Claim 18

Apparatus according to claim 13, characterized in that the retaining means comprises a dielectric vessel (30) for the fluid composite material disposed downstream from an outlet from the mixing device (18).

Claim 19

Apparatus according to claim 13 for controlling the quantity of particles in the composite material providing a dry dielectric layer upon a conductor, characterized in comprising an applicator (12) to apply the fluid composite material as a fluid layer to the conductor (14) as the conductor moves along a pass line; a drying oven (60) downstream of the applicator along the conductor pass line to dry the material into the dry dielectric layer; and the retaining means comprising a guide (58) for the layer covered conductor, the guide disposed downstream from the oven and surrounded by the coil (28).