Systems and methods for welding

Patent metadata

Field	Value
Publication number	US-2018141156-A1
Application number	US-201515570525-A
Country	US
Kind code	A1
Filing date	Jun 26, 2015
Priority date	Jun 26, 2015
Publication date	May 24, 2018
Grant date	—

Abstract

A laser welding system is provided. The laser welding system includes a laser source configured to produce a laser beam, a beam modifier configured to split the laser beam into at least two heat source points positioned at a predetermined angle relative to one another along a diagonal intersecting and radially equidistant from a center of a circular weld line, the circular weld line being concentric with an object to be welded, a rotation unit configured to cause rotation of the at least one group of two heat source points or the object to be welded, and a controller configured to control the rotation unit to cause the at least one group of two heat source points to scan substantially all of the circular weld line.

First claim

1 . A laser welding system, comprising:
a laser source configured to produce a laser beam; a beam modifier configured to split the laser beam into at least two heat source points positioned at a predetermined angle relative to one another and radially equidistant from a center of a circular weld line, the circular weld line being concentric with an object to be welded; a rotation unit configured to cause rotation of the at least two heat source points or the object to be welded; and a controller configured to control the rotating means to cause the at least two heat source points to scan substantially all of the circular weld line.

2 . The laser welding system according to claim 1 , wherein the at least two heat source points are positioned opposite one another along a diagonal intersecting the center of the circular weld line.

3 . The laser welding system according to claim 1 , wherein the predetermined angle is 180 degrees.

4 . The laser welding system according to claim 1 , wherein the beam modifier is configured to split the laser beam to produce at least two groups of two heat source points, the two heat source points of a second of the at least two groups being offset by 90 degrees from the two heat source points of a first of the at least two groups.

5 . The laser welding system according to claim 1 , wherein the rotation unit is configured to rotate the at least two heat source points through at least 90 degrees but not more than 180 degrees.

6 . The laser welding system according to claim 1 , wherein the rotation unit is operably connected to the beam modifier to cause rotation of the beam modifier.

7 . The laser welding system according to claim 1 , wherein the rotation unit is configured to rotate the object to be welded through at least 90 degrees but not more than 180 degrees.

8 . The laser welding system according to claim 1 , wherein the beam modifier comprises a diffractive optical element.

9 . The laser welding system according to claim 1 , wherein the object to be welded comprises an electrolyte fill-hole cap of a battery.

10 . The laser welding system according to claim 1 , wherein the at least one group of two heat source points is transmitted to the object to be welded without being reflected by a mirror.

11 . A method for laser welding, comprising:
splitting a laser beam into at least two heat source points, the at least two heat source points being positioned at a predetermined angle relative to one another and radially equidistant from a center of a circular weld line, the circular weld line being concentric with an object to be welded; and rotating the at least two heat source points about the center of the circular weld line, or rotating the object to be welded such that the at least two heat source points scan substantially the entire circular weld line.

12 . The method according to claim 11 , wherein the at least two heat source points are positioned opposite one another along a diagonal intersecting the center of the circular weld line.

13 . The method according to claim 11 , wherein the splitting results in at least two groups of two heat source points, the two heat source points of a second of the at least two groups being offset by 90 degrees from the two heat source points of a first group of the at least two groups.

14 . The method according to claim 11 , wherein the at least two heat source points or the object to be welded is rotated through at least 90 degrees but not more than 180 degrees.

15 . The method according to claim 11 , wherein the splitting comprises passing the laser beam through a diffractive optical element.

16 . The method according to claim 15 , comprising rotating the diffractive optical element.

17 . An electrolyte fill-hole cap of a battery welded to a battery case according to the method of claim 11 .

18 . The laser welding system according to claim 8 , wherein the diffractive optical element comprises a diffractive grating.

19 . The method according to claim 15 , where the diffractive optical element comprises a diffractive grating.

Assignees

• Toyota Motor Europe
• Toyota Motor Co Ltd

Inventors

• Tsukui Akira
• Nakayama Takayuki

Classifications

• H01M50/645

  Plugs · CPC title

• H01M50/627

  Filling ports · CPC title

• H01M50/147

  Lids or covers · CPC title

• H01M2/365

  Electricity · mapped topic

• B23K26/206 Primary

  Laser sealing · CPC title