Device and method for homogeneously welding two-dimensionally bent structures by friction stir welding

Patent metadata

Field	Value
Publication number	US-10583520-B2
Application number	US-201615751019-A
Country	US
Kind code	B2
Filing date	Aug 10, 2016
Priority date	Aug 13, 2015
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

The invention relates to a device and to a method for homogeneously welding two-dimensionally bent structures by friction stir welding.

First claim

The invention claimed is:

1. A device for homogeneously welding two-dimensionally bent structures in a form of at least two mating partners ( 6 ) by friction stir welding, the device comprising:
a receptacle plate ( 1 ) configured to be guided by a guiding machine;
a drive head ( 2 );
a tool dome ( 3 ); wherein the tool dome is fastened to said drive head ( 2 );
a welding shoe mounting ( 4 ); and
a pin bearing ( 5 ) adapted for a welding pin ( 11 ) of a welding shoe ( 8 );
wherein the welding shoe ( 8 ) comprises a circular shape on which a transverse web is located, the transverse web running across a cross section of and orthogonally to said circular shape,
wherein said transverse web comprises:
a width of approximately ¼ to ⅕ of a diameter of the circular shape, and
an arcuate shoe gliding face and shoe smoothing face,
wherein a small planar face in the form of a notch-type taper, the chip-guiding step ( 9 ), is located on the front side of the small planar face, in a peripheral region of the small planar face, and
wherein the shoe gliding face and the shoe smoothing face corresponds substantially to the surface curvature of the mating partners ( 6 );

wherein the tool dome ( 3 ) comprises:
a strip-shaped sensor ( 23 ) configured for determining force, pressure, or travel and is attached to a side of the tool dome ( 3 ) that is opposite to a flow direction of the welding process, and
wherein a cone constriction ( 17 ) is provided in a wide region of a tool receptacle cone ( 26 ), said cone constriction ( 17 ) serving for receiving a sensor ( 20 ) for acquiring axial force, torque, and bending momentum on the welding pin ( 11 ), and
wherein a further constriction in a front region of the tool receptacle cone ( 26 ) comprises at least three sensors ( 25 ), distributed at a spacing of 120 degrees on a circumference, for measuring the axial force acting on the welding pin ( 11 ), and a piezoelectric force measuring sensor ( 24 ), for measuring the axial force, is provided in a longitudinal axis of the shaft ( 7 ) of the friction pin, and
wherein a sensor signal amplifier having a rotary antenna ( 21 ) for receiving, for amplifying, and for transmitting all acquired measured values is provided,
wherein measured values are transmitted from a static antenna ( 22 ) to a machine controller, and
wherein an induction power supply system for supplying a measuring system from a moving secondary coil ( 19 ) and from a fixed stationary primary coil ( 18 ) is provided.

2. The device as claimed in claim 1 , further comprising a sensor adapted to detect a temperature of the welding pin ( 11 ) and/or of the welding shoe ( 8 ).

3. A method for homogeneously welding two-dimensionally bent structures in the form of at least two mating partners ( 6 ) by friction stir welding, the method comprising:
providing two-dimensionally bent structures in the form of at least two mating partners;
providing a device for friction stir welding as claimed in claim 2 ;
providing a strip-shaped sensor ( 23 ) along the side of the tool dome ( 3 ) for detecting force, pressure, or travel,
providing a sensor ( 20 ) for acquiring axial force, torque, and bending momentum on the welding pin ( 11 ),
measuring the axial force acting on the welding pin ( 11 ) with at least three sensors ( 25 ) in the form of strain gauge strips that are distributed on the circumference of the tool receptacle cone, and
providing a piezoelectric force measuring sensor ( 24 ) in the longitudinal axis of the shaft ( 7 ) of the friction pin, said piezoelectric force measuring sensor ( 24 ) adapted for measuring the axial force; and
contacting the device for friction stir welding with the two-dimensionally bent structures in the form of at least two mating partners to form a weld seam.

4. The method as claimed in claim 3 , further comprising measuring and closed-loop controlling the axial force acting on the welding pin ( 11 ),
measuring and closed-loop controlling the torque acting on the welding pin ( 11 ), and
adjusting the length of the welding pin ( 11 ), and
measuring the temperature on the welding pin ( 11 ).

5. The method as claimed in claim 3 , further comprising measuring and closed-loop controlling the compression force acting on the welding shoe ( 8 );
advancing the welding shoe ( 8 ) based on the measured axial force acting on the welding pin ( 11 ); and
measuring the temperature of said welding shoe ( 8 ).

6. The method as claimed in claim 3 , further comprising, prior to measuring the axial force acting on the welding pin, measuring parameters for controlling the welding process to provide a welding result that is free of holes on both sides of the mating partners ( 6 ).

7. The method as claimed in claim 4 , wherein the length of the welding pin is adjusted automatically by one or a plurality of piezoelectric actuator elements.

8. The method as claimed in claim 4 , wherein an infrared sensor is used to measure the temperature on the welding pin ( 11 ).

9. The method as claimed in claim 5 , wherein a temperature sensor is used to measure the temperature of said welding shoe ( 8 ).

10. The method as claimed in claim 5 , further comprising monitoring the weld seam for configuration and profile during the contacting step.

11. The method of claim 10 , wherein the configuration and profile for the weld seam is based on corresponding parameters of the at least two mating partners ( 6 ).

Assignees

• Grenzebach Maschb Gmbh
• Grenzebach Maschb

Inventors

• Weigl Markus

Classifications

• B23K20/1255

  Tools therefor, e.g. characterised by the shape of the probe · CPC title

• B23K20/1235 Primary

  with temperature control during joining · CPC title

• B23K20/1245

  characterised by the apparatus · CPC title

• B23K37/0276

  for working on or in tubes (B23K37/0211 takes precedence) · CPC title

• B23K20/129

  specially adapted for particular articles or work · CPC title