Device and method for contacting a welding rod and contact shell

Patent metadata

Field	Value
Publication number	US-9539663-B2
Application number	US-99857709-A
Country	US
Kind code	B2
Filing date	Nov 27, 2009
Priority date	Nov 27, 2008
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

The invention relates to a device and a method for contacting a welding wire ( 13 ) in a welding torch ( 10 ), including at least two contact shells ( 31 ) having a contact area ( 32 ) for contacting the welding wire ( 13 ), and to a contact shell ( 31 ) for contacting a welding wire ( 13 ). In order to make the contact of the welding wire as constant and permanent as possible during the lifetime of a contacting device, the contact shells ( 31 ) have a holding section ( 48 ) and are arranged inside a sleeve ( 37 ) to define a rotational axis ( 43 ), the sleeve ( 37 ) being fastened to a nozzle pipe ( 38 ) having an integrated pressure mechanism ( 36 ), and the pressure mechanism ( 36 ) being adapted to exert pressure ( 33 ) on the contact shells ( 31 ). The sleeve ( 37 ) includes a holding device ( 42 ) for exerting a counter-force ( 34 ) onto the contact shells ( 31 ). The welding wire ( 13 ) is contacted in the contact area ( 32 ) of the contact shells ( 31 ) with a contact force ( 35 ).

First claim

The invention claimed is:

1. A device for contacting a welding wire in a welding torch, the device comprising:
a) a nozzle pipe ( 38 );
b) a pressure mechanism ( 36 ) integrated in said nozzle pipe ( 38 );
c) a sleeve ( 37 ) fastened to said nozzle pipe ( 38 ); said sleeve ( 37 ) comprising a holding device ( 42 ); and
d) at least two contact shells ( 31 ) arranged inside said sleeve ( 37 ) and movable about a rotational axis ( 43 ) oriented substantially perpendicular to a longitudinal axis of said contact shells ( 31 ), each of said at least two contact shells ( 31 ) comprising:
i) a contact area ( 32 ) disposed at a front end of said contact shell ( 31 ) at which front end the welding wire exits said contact shell, said contact area ( 32 ) contacting the welding wire with a radially-effecting contact force ( 35 ); and
ii) a holding section ( 48 ) disposed opposite said contact area ( 32 ) at a rear end of said contact shell ( 31 ) at which rear end the welding wire enters said contact shell ( 31 ), the holding section comprising:
a front face ( 45 ) having a base area formed as a substantially circular segment and two contact points ( 47 ) disposed at opposite ends of a chord of said substantially circular segment, said rotational axis ( 43 ) corresponding to said chord connecting said two contact points ( 47 ); and

an elevation ( 46 ) positioned parallel to and above said rotational axis ( 43 ), said elevation ( 46 ) dividing said front face ( 45 ) into separate sections dropping obliquely starting from said elevation ( 46 ), thereby forming an outer clearance ( 49 ) between said front face ( 45 ) and said pressure mechanism ( 36 );

wherein when said pressure mechanism exerts an axial pressure ( 33 ) on said elevation ( 46 ) of said contact shells ( 31 ), said contact points ( 47 ) of said contact shells ( 31 ) are pressed against said holding device ( 42 ) of said sleeve ( 37 ), producing a counter-force ( 34 ) acting substantially on the ends of the rotational axis ( 43 ), the axial pressure ( 33 ) is converted into the radially-effecting contact force ( 35 ) via the counter-force ( 34 ) and the outer clearance ( 49 ) has a maximum height; and
wherein when the welding wire is conveyed through said contact shells ( 31 ), said contact shells ( 31 ) are pressed apart in said contact area ( 32 ) substantially normal to the welding wire and said outer clearance ( 49 ) is reduced.

2. The device according to claim 1 , wherein guides are provided for guiding the welding wire upstream and downstream of the contact area.

3. The device according to claim 1 , wherein the contact shells are movable in the contact area by the contact force substantially normally to the welding wire.

4. The device according to claim 1 , wherein the holding section is designed as the area of entry of the welding wire and comprises an oval and convex front face, and wherein the pressure is exerted on at least a part of the front face.

5. The device according to claim 1 , wherein the holding section is designed to be widened vis-à-vis the further contact shell, and wherein the transition to the widening is designed conically.

6. The device according to claim 1 , wherein the sleeve comprises a recess substantially corresponding to the contact shells.

7. The device according to claim 1 , wherein an insulation bushing for guiding the welding wire is provided in the sleeve.

8. The device according to claim 1 , wherein a guide pipe for the welding wire is arranged in the center of the pressure mechanism and in a part of the contact shells.

9. The device according to claim 1 , wherein the pressure mechanism is defined at least by a pressure bolt, a compression spring, and a fixing plate, and wherein the pressure bolt is movable substantially along the axis of the welding wire.

10. The device according to claim 1 , wherein it is designed for receiving contact shells.

11. A method for contacting a welding wire in a welding torch, the method comprising steps of:
a) providing a nozzle pipe ( 38 ), a pressure mechanism ( 36 ) integrated in the nozzle pipe ( 38 ), and a sleeve ( 37 ) fastened to the nozzle pipe ( 38 ), wherein the sleeve ( 37 ) comprises a holding device;
b) arranging at least two contact shells ( 31 ) inside the sleeve ( 37 ) and movably about a rotational axis ( 43 ) oriented substantially perpendicular to a longitudinal axis of the contact shells ( 31 ), wherein each of the at least two contact shells ( 31 ) comprises:
a contact area ( 32 ) disposed at a front end of the contact shell ( 31 ) at which front end the welding wire exits said contact shell, the contact area ( 32 ) contacting the welding wire with a radially-effecting contact force ( 35 ); and
a holding section ( 48 ) disposed opposite the contact area ( 32 ) at a rear end of the contact shell ( 31 ) at which rear end the welding wire enters the contact shell ( 31 ), the holding section comprising:
a front face ( 45 ) having a base area formed as a substantially circular segment and two contact points ( 47 ) disposed at opposite ends of a chord of the substantially circular segment, the rotational axis ( 43 ) corresponding to the chord connecting the two contact points ( 47 ); and
an elevation ( 46 ) positioned parallel to and above the rotational axis ( 43 ), the elevation ( 46 ) dividing the front face ( 45 ) into separate sections dropping obliquely starting from the elevation ( 46 ), thereby forming an outer clearance ( 49 ) between the front face ( 45 ) and the pressure mechanism ( 36 );

c) exerting a pressure ( 33 ) in an axial direction on a respective elevation ( 46 ) of the at least two contact shells ( 31 ), thereby pressing the two contact points ( 47 ) of the contact shells ( 31 ) against the holding device ( 42 ) of the sleeve ( 37 ) to generate a counter-force ( 34 ) and converting the pressure ( 33 ), via the counter-force ( 34 ), into the radially-effecting contact force ( 35 ) contacting the welding wire in the contact area ( 32 ), such that the outer clearance ( 49 ) has a maximum height; and
(d) conveying the welding wire through the contact shells ( 31 ), such that the contact shells ( 31 ) are pressed apart in the contact area ( 32 ) substantially normal to the welding wire and the outer clearance ( 49 ) is reduced.

12. The method according to claim 11 , wherein the axial pressure is exerted on each contact shell in places and in parallel to the rotational axis.

13. The method according to claim 11 , further comprising steps of:
providing a device for contacting a welding wire in a welding torch, the device comprising the at least two contact shells,
fastening the sleeve to a nozzle pipe having an integrated pressure mechanism, wherein the pressure mechanism is designed to exert the pressure on the contact shells and
forming the elevation for exerting the pressure in axial direction at the front face of the holding section of each contact shell,
wherein the contact shells are held movably in the sleeve via the two contact points.

Assignees

• Grossauer Wolfgang
• Hubinger Manfred
• Leonhartsberger Andreas
• Fronius Int Gmbh

Inventors

• Grossauer Wolfgang
• Hubinger Manfred
• Leonhartsberger Andreas

Classifications

• B23K9/1336

  Driving means · CPC title

• B23K9/287

  Supporting devices for electrode holders · CPC title

• B23K9/123 Primary

  Serving also as contacting devices supplying welding current to an electrode · CPC title

• B23K9/173

  and of a consumable electrode · CPC title