Induction sealing device and method which may be used for producing packages of pourable food products
First Claim
1. ) An induction sealing device which may be used for producing packages of pourable food products by transversely sealing a tube of sheet packaging material comprising at least one layer of induction heatable material covered with plastic material, said sealing device comprising:
- generating means for generating an alternating power signal;
at least one inductor receiving the alternating power signal to induce a parasitic electric current in said layer and locally melt said plastic material to form a transverse seal; and
a matching circuit for achieving optimum power transfer between said generating means and said inductor wherein said matching circuit comprises an inductive-capacitive circuit, in which at least one inductive element is connected to at least one variable-capacitance capacitive element;
the capacitance of the capacitive element being adjustable so that the current-voltage phase angle is close to zero.
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Accused Products
Abstract
An induction sealing device which may be used for producing packages of pourable food products by transversely sealing a tube of sheet packaging material having at least one layer of induction heatable material covered with plastic material. The sealing device has: a generator for generating an alternating power signal; an inductor receiving the alternating power signal to induce a parasitic electric current in the layer and locally melt the plastic material to form a transverse seal; and a matching circuit for achieving optimum power transfer between the generator and the inductor. The matching circuit includes an inductive-capacitive circuit, in which the capacitance of a variable capacitance capacitive element is adjustable so that the current-voltage phase angle is close to zero.
11 Citations
12 Claims
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1. ) An induction sealing device which may be used for producing packages of pourable food products by transversely sealing a tube of sheet packaging material comprising at least one layer of induction heatable material covered with plastic material, said sealing device comprising:
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generating means for generating an alternating power signal;
at least one inductor receiving the alternating power signal to induce a parasitic electric current in said layer and locally melt said plastic material to form a transverse seal; and
a matching circuit for achieving optimum power transfer between said generating means and said inductor wherein said matching circuit comprises an inductive-capacitive circuit, in which at least one inductive element is connected to at least one variable-capacitance capacitive element;
the capacitance of the capacitive element being adjustable so that the current-voltage phase angle is close to zero. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 12)
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10. ) An induction sealing method which may be used for producing packages of pourable food products by transversely sealing a tube of sheet packaging material comprising at least one layer of induction-heatable material covered with plastic material said method comprising the steps of:
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generating an alternating power signal by means of a generator;
supplying said alternating power signal to at least one inductor to induce a parasitic electric current in said layer and locally melt said plastic material to form a transverse seal; and
optimizing power transfer between said generator and said inductor by means of a matching circuit;
wherein said optimizing step comprises adjusting the capacitance of at least one capacitive element connected to at least one inductive element so that the current-voltage phase angle is close to zero. - View Dependent Claims (11)
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Specification