Galvanized multi-tubular beam and method of continuously forming the same

Patent metadata

Field	Value
Publication number	US-11427144-B2
Application number	US-201916695506-A
Country	US
Kind code	B2
Filing date	Nov 26, 2019
Priority date	Nov 27, 2018
Publication date	Aug 30, 2022
Grant date	Aug 30, 2022

Abstract

A galvanized reinforcement beam is continuously formed by uncoiling a roll of galvanized sheet stock in a generally horizontal plane. Protrusions are formed at an upper surface of the sheet stock, which is then roll formed to form a tubular shape with the protrusions abutting a surface of the sheet stock to form venting gaps. The sheet stock is laser welded at the protrusions to continuously form a weld joint, where zinc oxide gas generated from the welding is permitted to escape an interior of the tubular shape through the venting gaps.

First claim

The invention claimed is:

1. A galvanized multi-tubular beam for a vehicle structure or a bumper reinforcement, said galvanized multi-tubular beam manufactured by roll forming a galvanized metal sheet to form two adjacent tubular portions that share a common center wall of the beam, wherein outer sections of the metal sheet that form the two adjacent tubular portions extend from opposing sides of a center section of the metal sheet that forms the common center wall of the beam, said galvanized multi-tubular beam comprising:
an edge portion of one of the outer sections of the galvanized metal sheet attached to the center section of the galvanized metal sheet at a weld joint;
wherein the weld joint has a thickness that separates a planar surface of the edge portion from a planar surface of the center section;
wherein the thickness of the weld joint is formed by a plurality of protrusions that protrude from the planar surface of the outer section or the center section of the metal sheet;
wherein the plurality of protrusions each comprise a recessed portion protruding into the planar surface and a raised portion protruding from the planar surface; and
wherein, when welding the weld joint, a longitudinal spacing between the plurality of protrusions provides ventilation openings for zinc oxide fumes generated from the welding to escape an interior of the respective tubular portion of the beam.

2. The galvanized multi-tubular beam of claim 1 , wherein the weld joint extends continuously along the beam to enclose the interior of the respective tubular portion of the beam.

3. The galvanized multi-tubular beam of claim 1 , wherein the raised portion protrudes from the planar surface a height generally equal to a width of the ventilation openings.

4. The galvanized multi-tubular beam of claim 3 , wherein the plurality of protrusions are spaced at consistent intervals, and wherein the weld joint interconnects the plurality of protrusions.

5. The galvanized multi-tubular beam of claim 1 , wherein the weld joint has a narrow heat affect zone of approximately between 1 mm and 2 mm.

6. The galvanized multi-tubular beam of claim 1 , wherein a second edge portion of the galvanized metal sheet is attached at a side wall of the tubular portion of the beam that is generally perpendicular to the center wall of the beam.

7. The galvanized multi-tubular beam of claim 6 , wherein the second edge portion and the side wall are attached together at a laser welded lap joint.

8. The galvanized multi-tubular beam of claim 7 , wherein the laser welded lap joint includes a second thickness that separates a planar surface of the second edge portion from a planar surface of the side wall, and wherein the thickness of the weld joint is formed by a second plurality of protrusions that protrude from the planar surface of the second edge portion or the side wall, such that when welding the lap joint zinc oxide fumes escape the interior of the respective tubular portion of the beam through vent openings formed by the second plurality of protrusions.

9. The galvanized multi-tubular beam of claim 1 , wherein a separation between the edge portion and the center section that is formed at the weld joint is approximately between 50 micrometers and 300 micrometers.

10. The galvanized multi-tubular beam of claim 1 , wherein a length of each of the plurality of protrusions is approximately between 2 mm and 5 mm.

11. The galvanized multi-tubular beam of claim 1 , wherein a thickness of the metal sheet is approximately between 1 mm and 1.5 mm.

12. A method of continuously forming a galvanized reinforcement beam, said method comprising the steps of:
uncoiling a roll of galvanized sheet stock in a generally horizontal plane;
roll forming the sheet stock through a roll former comprising a set of a plurality of roll stations to form a tubular shape with an edge section of the sheet stock in contact with an intermediate section of the sheet stock;
forming protrusions over an upper surface of the sheet stock as the sheet stock moves in-line with the roll former;
wherein at least one of the edge section or the intermediate section of the sheet stock includes the protrusions, and wherein the protrusions form venting gaps between the edge section and the intermediate section of the sheet stock; and
laser welding an edge portion to an intermediate portion of the sheet stock at a laser head station to continuously form a weld joint, wherein zinc oxide gas generated from the welding is permitted to escape an interior of the tubular shape through the venting gaps.

13. The method of claim 12 , wherein the protrusions are spaced at generally consistent intervals and linearly disposed over the upper surface of the sheet stock.

14. The method of claim 12 , wherein the protrusions each comprise a raised portion that protrudes from the upper surface a height generally equal to a width of the venting gaps.

15. The method of claim 12 , wherein the protrusions are formed with at least one of laser dimpling, mechanical deformation, electrospark deposition, or additive material.

16. The method of claim 12 , wherein the sheet stock is uncoiled, roll formed, and welded in a longitudinal direction at a generally constant speed.

17. The method of claim 12 , wherein the protrusions are continuously formed at a station interposed in the set of the plurality of roll stations.

18. The method of claim 17 , wherein the protrusions are formed with a laser head station disposed between a first station and a last station of the set of the plurality of roll stations, so as to form the protrusions during the roll forming process.

19. A method of continuously forming a galvanized reinforcement beam, said method comprising the steps of:
uncoiling a roll of galvanized sheet stock in a generally horizontal plane;
feeding the sheet stock from the roll to a roll former in the generally horizontal plane;
roll forming the sheet stock in the roll former to form a tubular shape with the protrusions abutting a surface of the sheet stock to form venting gaps;
forming protrusions over an upper surface of the sheet stock as the sheet stock moves in-line with the roll former; and
laser welding the sheet stock at the protrusions to continuously form a weld joint, wherein zinc oxide gas generated from the welding is permitted to escape an interior of the tubular shape through the venting gaps.

20. A galvanized multi-tubular beam, said galvanized multi-tubular beam manufactured by roll forming a galvanized metal sheet to form two adjacent tubular portions that share a common center wall of the beam, said galvanized multi-tubular beam comprising:
an edge portion of an outer section of the galvanized metal sheet attached via a weld joint to a reinforcement rib formed at center section of the galvanized metal sheet, wherein the edge portion of the galvanized metal sheet forms the common center wall of the beam;
wherein the weld joint has a thickness that separates a planar surface of the edge portion from a planar surface of the reinforcement rib;
wherein the thickness of the weld joint is formed by a plurality of protrusions that protrude from the planar surface of at least one of the edge portion or the reinforcement rib;
wherein the plurality of protrusions each comprise a recessed portion protruding into the planar surface and a raised portion protruding from the planar surface; and
wherein, when welding the weld joint, a longitudinal spacing between the plurality of protrusions provides ventilation openings f

Assignees

• Shape Corp

Inventors

• Baas Douglas S
• Matecki Joseph R
• Jasman Shawn R

Classifications

• B60R19/18 Primary

  {characterised by the cross-section;} Means within the bumper to absorb impact · CPC title

• B21D5/086 Primary

  for obtaining closed hollow profiles · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B23K2101/006

  Vehicles · CPC title

• B23K26/354

  by melting · CPC title