US 7,399,946 B2
	Apparatus for generating a rotating laser beam
Joachim Hertzberg, Thun (Switzerland); Hans Peter Schwob, Uetendorf (Switzerland); Friedrich Durand, Solothurn (Switzerland); Walter Zürcher, Aarau (Switzerland); and Knobel Bruno, Laufen (Switzerland)
Assigned to LASAG AG, Thun (Switzerland)
Appl. No. 10/557,047 PCT Filed May 13, 2004, PCT No. PCT/EP2004/050798 § 371(c)(1), (2), (4) Date Nov. 27, 2006, PCT Pub. No. WO2004/101212, PCT Pub. Date Nov. 25, 2004.
Claims priority of application No. 03011210 (EP), filed on May 16, 2003.
Prior Publication US 2007/0080147 A1, Apr. 12, 2007
Int. Cl. B22K 26/06 (2006.01)

U.S. Cl. 219—121.74  [219/121.63; 219/121.75]

22 Claims

1. An apparatus for generating a rotating laser beam, in particular for circular welding and/or machining workpieces, said apparatus comprising input means for a laser beam, said laser beam following an optical path through at least one optical system of the apparatus before emerging from said apparatus through an output and impinging onto an impact region of a workpiece, said optical system having a central axis and being intended at least to adjust the position of an image focal point of said laser beam in said impact region, said optical system further comprising a first reflecting surface able to rotate about said central axis and intended to redirect said laser beam into the direction of a second reflecting surface of annular shape and intended to reflect said laser beam toward said axis, the apparatus comprising means for driving said first reflecting surface in rotation, wherein said optical system comprises at least one lens which makes said laser beam be convergent before it impinges on said first reflecting surface such as to form a first focal point in the vicinity of said first reflecting surface, distinct from the image focal point of said laser beam in said impact region of the workpiece.