Welding station for an installation for manufacturing packages with pads

1. A welding station for an installation for manufacturing packages with pads, the welding station comprising a plurality of longitudinal welding heads,

each longitudinal welding head being configured to weld to one another two superposed sheets as said sheets advance in a first direction and comprising a welder to apply heat at a determined action area of said welding head or facing said welding head,

each longitudinal welding head further comprising a first traction belt and a second traction belt parallel to the first traction belt and separated from the first traction belt by a determined separation gap in a second direction which is transverse to the first direction, the action area being arranged in said separation gap between both traction belts, or facing said separation gap, and

each of the longitudinal welding heads being configured to be moved along the second direction.

2. The welding station according to claim 1 , each longitudinal welding head comprising a first drive wheel with a first central shaft extending in the second direction and a second drive wheel with a second central shaft parallel to the first central shaft and distant from said first central shaft in the first direction, both traction belts being wound in both drive wheels.

3. The welding station according to claim 2 , each longitudinal welding head comprising a separating element joined to, or arranged in, each of the drive wheels, the first traction belt being on one side of said separating element with respect to the corresponding central shaft and the second traction belt being on the other side of said separating element, said separating element comprising a width in the second direction equal to the width of the separation gap.

4. The welding station according to claim 3 , an outer surface of the separating element of each longitudinal welding head being at the same level as an outer surface of the traction belts or is of a malleable material projecting from said outer surface of the traction belts of the corresponding longitudinal welding head.

5. The welding station according to claim 2 , each drive wheel comprising a respective groove for each traction belt, each groove being configured to house the corresponding traction belt and both grooves of one and the same drive wheel being separated by a distance equal to the width of the separation gap.

6. The welding station according to claim 2 , the two drive wheels of each welding head being gear wheels and the traction belts comprising a configuration complementary to the teeth of said drive wheels.

7. The welding station according to claim 1 , each longitudinal welding head comprising a holding-down device with at least one hold-down member arranged downstream of the action area in the first direction and configured to press the welded sheets.

8. The welding station according to claim 7 , each holding-down device comprising a plurality of hold-down members arranged in series in the first direction.

9. The welding station according to claim 8 , the hold-down members being configured to independently control a pressure force which they carry out on the sheets.

10. The welding station according to claim 7 , each longitudinal welding head comprising a cooler for cooling the separation gap present between both traction belts of the corresponding longitudinal welding head, downstream of the holding-down device in the first direction.

11. The welding station according to claim 1 , each longitudinal welding head comprising a cooler for cooling the separation gap present between both traction belts of the corresponding longitudinal welding head, at least downstream of the action area in the first direction.

12. The welding station according to claim 1 , the welder comprising a laser emitter emitting a laser beam towards the action area, directly or by one or more additional elements arranged to redirect said laser beam towards said action area.

13. The welding station according to claim 1 , comprising a support associated with at least one of the longitudinal welding heads,

said support being faced to said longitudinal welding head and configured so that the sheets move on it in the first direction, the support and the head being arranged such that the sheets move between the traction belts and said support, and

the at least one welding head comprising an actuator arranged upstream of the action area in the first direction and configured to push the sheets to be welded against the support, the actuator comprising a wheel and the support comprising a depression complementary with the wheel of the actuator and facing said wheel.

14. The welding station according to claim 1 , a support associated with at least one of the longitudinal welding heads,

said support being faced to said longitudinal welding head and configured so that the sheets move in the first direction between said support and the head,

the support and the head facing one another and said support being selected from a support surface, said support surface and the head being arranged such that the traction belts of the head press the sheets against said support surface; and

a support head comprising a first drive wheel with a first central shaft extending in the second direction and a second drive wheel with a second central shaft extending parallel to the first central shaft and distant from said first central shaft in the first direction, a first traction belt wound in both drive wheels, and a second traction belt wound in both drive wheels in parallel to the first traction belt and separated from the first traction belt by the separation gap in the second direction,

said support head and the head being arranged such that the sheets are pressed between the corresponding traction belts of both heads,

the support head further comprising a support surface which is at the same level as the traction belts of said support head, in the part of said traction belts facing the welding head, said support surface being facing the welding area.

15. An installation for manufacturing packages with pads, the installation comprising a welding station for an installation for manufacturing packages with pads and the welding station comprising a plurality of longitudinal welding heads,

each longitudinal welding head being configured to weld to one another two superposed sheets as said sheets advance in a first direction and comprising a welder to apply heat at a determined action area of said head or facing said head,

each longitudinal welding head further comprising a first traction belt and a second traction belt parallel to the first traction belt and separated from the first traction belt by a determined separation gap in a second direction which is transverse to the first direction, the action area being arranged in said separation gap between both traction belts, or facing said separation gap, and

each of the longitudinal welding heads being configured to be able to be moved along the second direction.