Machine for forming filter bags for infusion products

Patent metadata

Field	Value
Publication number	US-11377243-B2
Application number	US-201916973683-A
Country	US
Kind code	B2
Filing date	Jun 19, 2019
Priority date	Jun 20, 2018
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

A machine for making filter bags of different shapes for infusion products includes: a wheel defining a work surface and rotating about a relative axis; feed stations for placing tags on the work surface, a continuous thread, along a weave path, and a strip of filter material superposing the weave of thread and the tag. A sealing device is located downstream of the feed stations for sealing between the thread, tag and strip of filter material. A feed device moving the strip along a feed line is positioned downstream of the wheel. A station introduces a dose of infusion product in bag and closes the bag. The feed device has two feed rollers, for unwinding the strip, controlled by a control system for adjusting the speed of rotation of the feed rollers as a function of the length of the filter material needed to form the bag.

First claim

The invention claimed is:

1. A machine for making filter bags for infusion products, each filter bag including a piece of filter material to which is associated a tie thread for connection with a gripping tag; the machine for making filter bags comprising:
a wheel defining a work surface; the wheel being rotational about a wheel axis to define a working path having a circular feed direction;
a first feed station configured for depositing individual tags, in phase, on the work surface in a depositing zone of the working path;
a second feed station configured for feeding, along a weave path, a thread on the work surface, starting from a further zone downstream of the depositing zone with reference to the feed direction of the wheel;
a third feed station configured for feeding a continuous strip of filter material on the work surface superposing the weave of thread and the tag, and positioned downstream relative to the second feed station with reference to the feed direction of the wheel;
a sealing device, positioned downstream of the first and second feed stations with reference to the feed direction of the wheel, and configured to provide seals between the thread, the tag and the strip of filter material;
a first feed device configured for moving the strip of filter material along a feed line, and positioned downstream of the wheel with reference to a feed direction of the strip of filter material;
a completion station configured for completing the filter bag equipped with the tag and the thread, the completion station positioned downstream of the first feed device with reference to the feed direction of the strip of filter material, and configured for forming the filter bag, for introducing a dose of infusion product in the filter bag formed and for closing the filter bag containing the dose of infusion product, wherein the first feed device comprises two first feed rollers configured for unwinding in a controlled manner, a quantity of the strip of filter material to be placed on the work surface of the wheel, the two first feed rollers being controlled by a control system for adjusting, via a motor, a speed of rotation of the two first feed rollers as a function of a length of the piece of filter material needed to form the filter bag of a desired size, and
a transfer device configured for transversely moving the strip of filter material being fed, to modify a position of a centerline axis of the strip of filter material, such that the centerline axis coincides with a working line on the work surface of the wheel; the working line being parallel to the feed line and defined as a function of the desired size of the filter bag.

2. The machine according to claim 1 , wherein the two first feed rollers are configured to operate with an alternating or step-by-step rotary movement.

3. The machine according to claim 1 , and further comprising a second feed device configured for moving the strip of filter material, positioned between the first feed device and the completion station; the second feed device having two second rollers configured for feeding and positioning, in a controlled manner, the strip of filter material in the completion station.

4. The machine according to claim 3 , wherein the two second rollers are configured to operate with a continuous rotary movement.

5. The machine according to claim 3 , and further comprising a compensating device configured for modulating the feeding of the strip of filter material; the compensating device being positioned between the first feed device and the second feed device for modulating the feeding of the feed strip of material between the first feed device and the second feed device as a function of different speeds for feeding the strip of filter material of the first feed device and the second feed device.

6. The machine according to claim 1 , wherein the transfer device comprises a transfer roller articulated to a unit for moving and intercepting the strip of filter material being fed, an angular rotation of the transfer roller being configured to modify a position of the centerline axis of the strip of filter material.

7. The machine according to claim 1 , wherein the wheel has a prismatic shape such that the work surface defines a plurality of individual work surfaces in succession about the wheel axis; each individual work surface being flat in extension in such a way as to move, in sequence, to the individual first, second and third feed stations.

8. The machine according to claim 7 , wherein the wheel has an octagonal shape, in cross section, to form eight individual work surfaces.

9. The machine according to claim 7 , wherein each individual work surface has a plurality of projecting reference pins for defining the weave path of the thread.

10. The machine according to claim 1 , wherein the sealing device comprises:
a first sealing device, positioned between the second feed station and the third feed station, and configured for making a first series of seals between the thread and the tag; and
a second sealing device, positioned downstream of the first sealing device, with reference to the feed direction of the wheel, and configured for making a plurality of seals between a portion of the thread, positioned according to the weave path, and the strip of filter material, and between the strip of filter material and the tag.

11. The machine according to claim 10 , wherein each first and second sealing device includes a respective single head for ultrasonic sealing, each acting on a corresponding portion of the work surface of the wheel.

12. The machine according to claim 1 , wherein the control system is operatively connected with a memory on which is stored a plurality settings for a respective plurality of speeds of rotation of the two first feed rollers.

13. A machine for making filter bags for infusion products, the machine comprising:
a wheel having a work surface rotatable about an axis of rotation;
a filter feed station configured to feed a continuous strip of filter material on the work surface of the wheel;
a drawing device configured to advance the strip of filter material along a direction of advancement of the strip of filter material and arranged downstream of the wheel with reference to the direction of advancement of the strip of filter material;
a filter bag forming station arranged downstream of the drawing device with reference to the direction of advancement of the strip of filter material, and configured to introduce a dose of infusion product in the filter bag formed, and to close the filter bag containing the dose of infusion product,
wherein the drawing device is configured to draw the strip of filter material at a speed which is a function of a length of the piece of filter material needed to form the filter bag of a desired size, and
a transfer device for moving the strip of filter material transversely with respect to the direction of advancement of the strip of filter material in order to shift a position of a centerline axis of the strip of filter material such that the centerline axis of the strip of filter material coincides with a working line on the work surface of the wheel; the working line being parallel to the direction of advancement of the strip of filter material and defined as a function of the desired size of the filter bag.

Assignees

• Ima Spa

Inventors

• Rivola Sauro
• Sermenghi Andrea
• Bianchi Mauro

Classifications

• B65H23/038

  by rollers · CPC title

• B65B41/18

  Registering sheets, blanks, or webs · CPC title

• B65B29/028 Primary

  packaging infusion material into filter bags · CPC title

• B65B41/16

  by rollers · CPC title

• B65B59/02

  Arrangements to enable adjustments to be made while the machine is running · CPC title