Laser nozzle having an external mobile element

Patent metadata

Field	Value
Publication number	US-9604310-B2
Application number	US-201314441565-A
Country	US
Kind code	B2
Filing date	Oct 23, 2013
Priority date	Nov 9, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

The invention relates to a nozzle for laser cutting, comprising a nozzle body ( 1 ) comprising a first axial passage ( 5 ); an external cover ( 13 ) comprising an axial housing ( 7 ), the nozzle body ( 1 ) being arranged at least partially in said axial housing ( 7 ); a movable element ( 3 ) comprising a second axial passage ( 4 ) and a front portion ( 3 a ) forming a skirt, said movable element ( 3 ) being arranged between the external cover ( 13 ) and the nozzle body ( 1 ) and being translationally movable in the axial housing ( 7 ) of the external cover ( 13 ); and an elastic element ( 8 ) arranged in the axial housing ( 7 ), between the external cover ( 13 ) and the nozzle body ( 1 ). According to the invention, the movable element ( 3 ) is able and designed to move translationally in the axial housing ( 7 ) in the direction of the first outlet orifice ( 14 ) under the effect of a gaseous pressure of said assistance gas ( 23 ), said pressure being applied in said axial housing ( 7 ) and exerted on said movable element ( 3 ), said elastic element ( 8 ) exerting an elastic return force on the movable element ( 3 ) tending to oppose the translational movement of the movable element ( 3 ). Associated laser head and apparatus. Laser cutting process employing such a nozzle.

First claim

The invention claimed is:

1. A laser nozzle comprising:
a nozzle body comprising a first axial passage and an inlet orifice allowing said first axial passage to be supplied with assistance gas;
an external cover comprising an axial housing and a first outlet orifice located in a front face of said external cover, the nozzle body being arranged at least partially in said axial housing;
a movable element comprising a second axial passage and a front portion forming a skirt, said movable element being arranged between the external cover and the nozzle body and being translationally movable in the axial housing of the external cover; and
an elastic element arranged in the axial housing, between the external cover and the nozzle body,

wherein the movable element is able and designed to move translationally in the axial housing in the direction of the first outlet orifice under the effect of a gaseous pressure of said assistance gas, said pressure being applied in said axial housing and exerted on said movable element, said elastic element exerting an elastic return force on the movable element tending to oppose the translational movement of the movable element in the axial housing in the direction of the first outlet orifice.

2. The nozzle of claim 1 , wherein the movable element is able and designed to move translationally in the axial housing in the direction of the first outlet orifice, until the front portion forming a skirt of the movable element protrudes out of the axial housing through said first outlet orifice of the axial housing.

3. The nozzle of claim 1 , wherein the nozzle body, the external cover and the movable element are axisymmetric parts arranged coaxially relative to one another, the nozzle body comprising a front portion arranged at least partially in the second axial passage of the movable element.

4. The nozzle of claim 1 , wherein the first axial passage of the nozzle body comprises a second outlet orifice located in the front portion of said nozzle body and the second axial passage of the movable element comprises a third outlet orifice located in the front portion forming a skirt of the movable element, said third outlet orifice opening downstream of said second outlet orifice when the front portion protrudes out of the axial housing.

5. The nozzle of claim 1 , wherein the nozzle body comprises at least one gas supply duct arranged within said nozzle body and bringing the first axial passage of the nozzle body and the axial housing of the external cover into fluidic communication.

6. The nozzle of claim 1 , wherein the axial housing comprises an internal shoulder, and the external peripheral wall of the movable element comprises an abutment arranged facing said internal shoulder, the elastic element being arranged between the abutment and the internal shoulder.

7. The nozzle of claim 1 , further comprising a tubular element forming a sleeve about all or some of the front portion of the nozzle body, the tubular element being formed from an electrically insulating material.

8. The nozzle of claim 1 , wherein the movable element is able to move between a plurality of positions comprising:
a rest position in which the front portion of the movable element is completely or almost completely retracted into the axial housing; and
a working position in which the skirt of the front portion of the movable element completely or almost completely protrudes out of the axial housing, through the third outlet orifice.

9. A laser focusing head comprising at least one focusing optical element, further comprising a laser nozzle as claimed in claim 1 .

10. A laser apparatus comprising a laser generator, a laser focusing head and a laser beam guiding device connected to said laser generator and to said laser focusing head, wherein the laser focusing head is as claimed in claim 9 .

11. The apparatus as claimed in claim 10 , further comprising a gas source and at least one gas supply line fluidically connecting the focusing head and said gas source, the first passage of the laser nozzle body being fluidically connected to the focusing head, and the movable element moving translationally in the axial housing of the nozzle body when the gas source supplies the focusing head and the laser nozzle.

Assignees

• L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude

Inventors

• Jouanneau Thomas
• Lefebvre Philippe

Classifications

• B23K26/048 Primary

  by controlling the distance between laser head and workpiece · CPC title

• B23K26/38

  by boring or cutting · CPC title

• B23K26/147 Primary

  Features outside the nozzle for feeding the fluid stream towards the workpiece · CPC title

• B23K26/1464

  Supply to, or discharge from, nozzles of media, e.g. gas, powder, wire · CPC title