Device for forming and applying at least one pair of accessory elements on a continuous band of absorbent material and machine for making absorbent sanitary articles comprising the device

Patent metadata

Field	Value
Publication number	US-10470940-B2
Application number	US-201515504929-A
Country	US
Kind code	B2
Filing date	Aug 4, 2015
Priority date	Aug 27, 2014
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

A device for forming and applying accessory elements to a continuous band of absorbent material, includes a unit for feeding a continuous strip to a conveyor roller, a unit for cutting the strip in a continuous and alternating succession of first and second pieces, a first and a second roller rotating about respective axes parallel to the first direction, each including a movement device acting along a circumferential direction around the respective axis and configured for imparting to each unit a respective motion between positions for picking up and releasing the pieces. A unit for applying a pair of pieces to the band is equipped with a separating unit equipped with a spacer device for moving first and/or second carriages along a separating direction between close and far axial positions, wherein the spacer device includes a plurality of linear actuators each associated with a respective first carriage.

First claim

The invention claimed is:

1. A device for forming and applying at least one pair of accessory elements to a continuous band of absorbent material, comprising:
a feeding unit for feeding a continuous strip to a conveyor roller, rotating about an axis transversal to a first direction,
a cutting unit for cutting the strip in a continuous and alternating succession of first and second pieces, comprising, respectively, first and second accessory elements of the absorbent article,
a first transfer roller and a second transfer roller rotating about respective axes parallel to the first direction and each equipped with a plurality of picking units for picking up, respectively, the first and the second pieces, from the succession at a picking up position and their release at a release position, wherein each of the first transfer roller and the second transfer roller comprises:
a movement device for moving the plurality of picking units, the movement device acting along a circumferential direction around the respective axis and configured for imparting to each of the plurality of picking units a respective motion between the picking up position for picking up the first and second pieces, located at the conveyor roller, and the position for releasing the first and second pieces;
a translating device for translating the plurality of picking units, the translating device acting along a direction parallel to the first direction and configured for moving each of the plurality of picking units between a first axial position, adopted in the picking up position, and a second axial position, adopted in the release position;
an application unit for applying the first and second pieces to the band of absorbent material including a separating unit configured for picking up one of the first pieces and one of the second pieces from the release position of the first transfer roller and the second transfer roller by respective first and second carriages; the separating unit including a spacer device suitable for moving at least one chosen from the first carriage and the second carriage along a separating direction parallel to the first direction between a close axial position, wherein each first carriage is aligned and located at a predetermined intermediate distance from a respective second carriage, and a far axial position wherein the carriages are located at an operating distance which is greater than the intermediate distance;
wherein the spacer device comprises:
a plurality of linear actuators each associated with the first carriage;
a further plurality of linear actuators each associated with the second carriage, wherein each of the plurality of linear actuators is opposite to and aligned with one of the further plurality of linear actuators.

2. The device according to claim 1 , wherein each linear actuator includes a linear electric motor.

3. The device according to claim 2 , wherein each linear actuator comprises a movable part and a fixed part, wherein the fixed part is defined by a wired guide, connected to a control unit and forming a motor of the linear actuator and the movable part is defined by a magnet slidable along the guide on which the carriage is anchored.

4. The device according to claim 1 , wherein the spacer device comprises a rotatable core on which the linear actuators are radially anchored and a rotation device operatively associated with the core.

5. The device according to claim 4 , wherein each linear actuator comprises a linear guide, oriented parallel to the separating direction and protruding radially from the rotatable core, on which at least one chosen from the first carriage and the second carriage is slidable.

6. The device according to claim 5 , and further comprising a vacuum device for generating a vacuum positioned in fluid communication with each of the first and second carriages; the first and second carriages including at least one operating suction surface associated with the vacuum device.

7. The device according to claim 6 , wherein the vacuum device comprises a plurality of conduits extending inside the guides of the carriages, each having an end section defined by an oblong opening made in the guide; the carriages each being equipped with a sealing tab slidably superposed on the oblong opening and shaped in such a way as to occlude the oblong opening in both the close and far axial positions of the respective carriage.

8. The device according to claim 1 , wherein the application unit further comprises an acceleration station operatively located downstream of the separating unit so as to receive the first and second piece positioned at the operating distance and configured to accelerate the feeding speed of the first and second piece in such a way as to be equivalent to a feeding speed of the continuous band of absorbent material.

9. The device according to claim 8 , wherein the acceleration station comprises at least one rotary unit including at least one seat for receiving the first and second pieces positioned at the operating distance and having a weight and dimensions less than that of the separating unit; the acceleration station also including a further movement device associated with the at least one rotary unit and configured for imparting to the at least one rotary unit a speed of rotation variable between a minimum value, wherein the at least one seat has a feed speed equal to a peripheral speed of the spacer device, and a maximum value, wherein the feeding speed of the at least one seat is equal to the feeding speed of the continuous band of absorbent material.

10. The device according to claim 9 , wherein the at least one rotary unit comprises a central core and at least one pair of radial arms, each extending away from the central core up to an end portion suitable for receiving the first and second pieces.

11. The device according to claim 1 , wherein the movement device for moving the plurality of picking units comprises a plurality of concentric units rotating independently of each other about a shared axis of rotation, each of the plurality of concentric units carrying at least one respective unit of the plurality of picking units and at least one motor for defining a respective motion for each of the plurality of concentric units.

12. A machine for making absorbent sanitary article, comprising:
the device for forming and applying the at least one pair of accessory elements on the continuous band of absorbent material according to claim 1 ;
a conveyor for feeding the continuous band of absorbent material along a second direction, at right angles to the first direction, facing the application unit of the device;
a further cutting unit for cutting the continuous band into pieces of absorbent material suitable for constituting single absorbent articles, following application of the accessory elements by the device for forming and applying the at least one pair of accessory elements on the continuous band of absorbent material.

Assignees

• Gdm Spa

Inventors

• Piantoni Matteo
• Soli Valerio

Classifications

• A61F13/15804

  Plant, e.g. involving several steps · CPC title

• A61F13/15764

  Transferring, feeding or handling devices; Drives · CPC title

• A61F13/15756 Primary

  Applying tabs, strips, tapes, loops; Knotting the ends of pads · CPC title

• H02K41/031

  of the permanent magnet type · CPC title

• A61F13/15723

  Partitioning batts; Cutting · CPC title