Patent ID: 6389781
Filing Date: 2002-05-21
Classification: B65B,B65D

Abstract:
A method of forming a two-lobed filter bag for products for infusion, the method comprising the following steps:evenly depositing doses of the products to be infused for infusion on the upper surface of a sheet of heat-sealable filter paper; folding the sheet of heat-sealable filter paper along a longitudinal axis; heat-sealing the folded sheet of heat sealable filter paper by a series of longitudinal and transversal seals, wherein a continuous sealed tubular sheet divided into individual lobes at regular distances from one another is defined, wherein each pair of lobes defines an individual filter bag; each filter bag being delimited by two different transversal end seals having longitudinal halves that include the two ends of the filter bag, and a complete intermediate seal between the two different transversal end seals that defines the base of each filter bag; depositing a continuous thread onto the upper surface of the tubular sheet, wherein the continuous thread includes a pick-up label attached to the thread at regular distances from the two lobes; defining a loop of thread lying on a half of one of the transversal seals, wherein an extensive contact surface between the continuous thread and the lobe is created; on a half of the other transversal seal includes a section of thread to which the pick-up label is attached; defining an additional portion of thread lying along a zig-zag path on the intermediate transversal seal; heat-sealing the looped length of thread to the upper surface of the tubular sheet at the half of the transversal seal without penetrating the thread through the sheet; heat-sealing the additional portion of thread to the upper surface of the tubular sheet at intermediate transversal seal without penetrating the thread through the sheet; heat-sealing the section of thread to which the pick-up label is attached to the upper surface of the tubular sheet without penetrating the thread through the sheet; cutting the transversal end seals into halves to define the two lobes of each filter bag; and folding the two lobes towards one another until the two free ends are heat-sealed together to define a filter bag packaging configuration in which the thread is wound longitudinally around the two lobes and attached at an end of thread to outer surfaces of the lobes.